Farhan Qureshi (R. Madhavan), Raju Rastogi (Sharman Joshi), and Rancchoddas "Rancho" Shyamaldas Chanchad (Aamir Khan) are three engineering students who share a room in a hostel at the Imperial College of Engineering, one of the best colleges in India. While Farhan and Raju are average students from modest backgrounds, Rancho is from a rich family. Farhan wants to become a wildlife photographer, but has joined engineering college to fulfil his father's wish. Raju on the other hand wants to uplift his family fortunes. Rancho is a wealthy genius who studies for the sheer joy of it. However, Rancho's passion is for knowledge and taking apart and building machines rather than the conventional obsession of the other students with exam ranks. With his different approach Rancho incurs the wrath of dean of college, Professor Viru Sahastrabudhhe (ViruS) (Boman Irani). Rancho irritates his lecturers by giving creative and unorthodox answers, and confronts ViruS after fellow student Joy Lobo hangs himself in his dormitory room. Joy had requested an extension on his major project on compassionate groundshis father had suffered a strokebut ViruS refused, saying that he himself was completely unmoved by his own son's accidental death after being hit by a train. Rancho denounces the rat race, dog-eat-dog, mindless rote learning mentality of the institution, blaming it for Lobo's death.
Threatened by Rancho's talent and free spirit, ViruS labels him an "idiot" and attempts on a number of occasions to destroy his friendship with Farhan and Raju, warning them and their parents to steer clear of Rancho. In contrast, ViruS model student is Chatur Ramalingam or "Silencer", (Omi Vaidya) who sees a high rank at the prestigious college as his ticket to higher social status, corporate power, and therefore wealth. Chatur conforms to the expectations of the system. Rancho humiliates Chatur, who is awarded the honour of making a speech at an award ceremony, by substituting obscenities into the text, which has been written by the librarian. As expected, Chatur mindlessly memorises the speech, without noticing that anything is amiss, partly aided by his lack of knowledge on Hindi. His speech becomes the laughing stock of the audience, infuriating the authorities in the process.
Meanwhile, Rancho also falls in love with ViruS' medical student daughter Pia (Kareena Kapoor) when he, Raju and Farhan crash her sister's wedding banquet in order to get a free meal, in the process further infuriating ViruS.
Meanwhile, the three students continue to anger ViruS, although Rancho continues to come first in every exam, while Chatur is always second, and Farhan and Raju are inevitably in the last two positions. The tensions come to a head when the three friends, who are already drunk, break into ViruS's house at night to allow Rancho to propose to Pia, and then urinate on a door inside the compound before running away when ViruS senses intruders. The next day, ViruS threatens to expel Raju lest he talks on the other two. Unable to choose between betraying his friend or letting down his family, Raju jumps out of the 3rd floor window and lands on a courtyard, but after extensive care from Pia and his roommates, awakes from a coma.
The experience has changed Farhan and Raju, and they adopt Rancho's outlook. Farhan decides to pursue his love of photography, while Raju takes an unexpected approach for an interview for a corporate job. He attends in plaster and a wheelchair and gives a series of non-conformal and frank answers. However, ViruS is unsympathetic and vows to make the final exam as hard as possible so that Raju is unable to graduate. Pia hears him and angrily confronts him, and when ViruS gives the same ruthless reply he gives to his students, she denounces him in the same way that Rancho did over the suicide of Lobo. Pia reveals that Viru's son and her brother was not killed in an accident but committed suicide in front of a train and left a letter because ViruS had forced him to pursue a career in engineering over his love for literature; ViruS always mentioned that he unsympathetically failed his son on the ICE entrance exams over and over to every new intake of ICE students. After this, Pia walks out on the family home, and takes ViruS's spare keys with her. She tells Rancho of the exam, and he and Farhan break into ViruS's office and steals the exam and give it to Raju, who with his new-found attitude, is unconcerned with the prospect of failing, and refuses to cheat and throws the paper away. However, ViruS catches the trio and expels them on the spot. However, they earn a reprieve when Viru's pregnant elder daughter Mona (Mona Singh) goes into labour at the same time. A heavy storm cuts all power and traffic, and Pia is still in self-imposed exile, so she instructs Rancho to deliver the baby in the college common room via VOIP, after Rancho restores power using car batteries and a power inverter that Rancho had dreamed up and ViruS had mocked. Rancho then delivers the baby with the help of a cobbled-together Vacuum extractor.
After the baby is apparently stillborn, Rancho resuscitates it. ViruS reconciles with Rancho and his friends and allows them to take their final exams and they graduate. Rancho comes first and is awarded ViruS's pen, which the professor had been keeping for decades before finding a brilliant enough student to gift it to.
Their story is framed as intermittent flashbacks from the present day, ten years after Chatur vowed revenge on Rancho for embarrassing him at the speech night and promised to become more successful than Rancho a decade later. Having lost contact with Rancho, who disappeared during the graduation party and went into seclusion, Raju and Farhan begin a journey to find him. They are joined by Chatur, now a wealthy and successful businessman, who joins them, brazenly confident that he has surpassed Rancho. Chatur is also looking to seal a deal with a famous scientist and prospective business associate named Phunsukh Wangdu. Chatur sees Wangdu, who has hundreds of patents, as his ticket to further social prestige. When they find Rancho's house, they walk into his father's funeral, and find a completely different Rancho Jaaved Jaffrey. After accusing the new man of stealing their friend's identity and profiting from his intellect, the host pulls a gun on them, but Farhan and Raju turn the tables by seizing the father's ashes and threatening to flush them down the toilet. The householder capitulates and says that their friend was a destitute servant boy who loved learning, while he, the real Rancho, was a lazy wealthy child who disliked study, so the family agreed to let the servant boy study in Rancho's place instead of labouring. In return, the real Rancho would pocket the qualifications and the benefits thereof, while the impersonator would sever all contact with the world and start a new life. The real Rancho reveals that his impersonator is now a schoolteacher in Ladakh.
Raju and Farhan then find Pia, and take her from her wedding day to Suhas by performing the same tricks with his material possessions, and having Raju turn up to the ceremony disguised as the groom and eloping with Pia in public. When they arrive in Ladakh, they see a group of enthusiastic Ladakhi children who are motivated by love of knowledge. Pia and the fake Rancho rekindle their love, while Chatur mocks and abuses Rancho the schoolteacher before walking away. When his friends ask what his real name is, he reveals that it Phunsukh Wangdu and phones Chatur, who has turned his back, to turn around and meet his prospective business partner. Chatur is horrified and falls to his knees, accepts his defeat and continues to plead his case with Phunsukh to establish the business relationship he was after.
Miyerkules, Hulyo 27, 2011
THE 3 IDIOTS
Farhan Qureshi (R. Madhavan), Raju Rastogi (Sharman Joshi), and Rancchoddas "Rancho" Shyamaldas Chanchad (Aamir Khan) are three engineering students who share a room in a hostel at the Imperial College of Engineering, one of the best colleges in India. While Farhan and Raju are average students from modest backgrounds, Rancho is from a rich family. Farhan wants to become a wildlife photographer, but has joined engineering college to fulfil his father's wish. Raju on the other hand wants to uplift his family fortunes. Rancho is a wealthy genius who studies for the sheer joy of it. However, Rancho's passion is for knowledge and taking apart and building machines rather than the conventional obsession of the other students with exam ranks. With his different approach Rancho incurs the wrath of dean of college, Professor Viru Sahastrabudhhe (ViruS) (Boman Irani). Rancho irritates his lecturers by giving creative and unorthodox answers, and confronts ViruS after fellow student Joy Lobo hangs himself in his dormitory room. Joy had requested an extension on his major project on compassionate groundshis father had suffered a strokebut ViruS refused, saying that he himself was completely unmoved by his own son's accidental death after being hit by a train. Rancho denounces the rat race, dog-eat-dog, mindless rote learning mentality of the institution, blaming it for Lobo's death.
Threatened by Rancho's talent and free spirit, ViruS labels him an "idiot" and attempts on a number of occasions to destroy his friendship with Farhan and Raju, warning them and their parents to steer clear of Rancho. In contrast, ViruS model student is Chatur Ramalingam or "Silencer", (Omi Vaidya) who sees a high rank at the prestigious college as his ticket to higher social status, corporate power, and therefore wealth. Chatur conforms to the expectations of the system. Rancho humiliates Chatur, who is awarded the honour of making a speech at an award ceremony, by substituting obscenities into the text, which has been written by the librarian. As expected, Chatur mindlessly memorises the speech, without noticing that anything is amiss, partly aided by his lack of knowledge on Hindi. His speech becomes the laughing stock of the audience, infuriating the authorities in the process.
Meanwhile, Rancho also falls in love with ViruS' medical student daughter Pia (Kareena Kapoor) when he, Raju and Farhan crash her sister's wedding banquet in order to get a free meal, in the process further infuriating ViruS.
Meanwhile, the three students continue to anger ViruS, although Rancho continues to come first in every exam, while Chatur is always second, and Farhan and Raju are inevitably in the last two positions. The tensions come to a head when the three friends, who are already drunk, break into ViruS's house at night to allow Rancho to propose to Pia, and then urinate on a door inside the compound before running away when ViruS senses intruders. The next day, ViruS threatens to expel Raju lest he talks on the other two. Unable to choose between betraying his friend or letting down his family, Raju jumps out of the 3rd floor window and lands on a courtyard, but after extensive care from Pia and his roommates, awakes from a coma.
The experience has changed Farhan and Raju, and they adopt Rancho's outlook. Farhan decides to pursue his love of photography, while Raju takes an unexpected approach for an interview for a corporate job. He attends in plaster and a wheelchair and gives a series of non-conformal and frank answers. However, ViruS is unsympathetic and vows to make the final exam as hard as possible so that Raju is unable to graduate. Pia hears him and angrily confronts him, and when ViruS gives the same ruthless reply he gives to his students, she denounces him in the same way that Rancho did over the suicide of Lobo. Pia reveals that Viru's son and her brother was not killed in an accident but committed suicide in front of a train and left a letter because ViruS had forced him to pursue a career in engineering over his love for literature; ViruS always mentioned that he unsympathetically failed his son on the ICE entrance exams over and over to every new intake of ICE students. After this, Pia walks out on the family home, and takes ViruS's spare keys with her. She tells Rancho of the exam, and he and Farhan break into ViruS's office and steals the exam and give it to Raju, who with his new-found attitude, is unconcerned with the prospect of failing, and refuses to cheat and throws the paper away. However, ViruS catches the trio and expels them on the spot. However, they earn a reprieve when Viru's pregnant elder daughter Mona (Mona Singh) goes into labour at the same time. A heavy storm cuts all power and traffic, and Pia is still in self-imposed exile, so she instructs Rancho to deliver the baby in the college common room via VOIP, after Rancho restores power using car batteries and a power inverter that Rancho had dreamed up and ViruS had mocked. Rancho then delivers the baby with the help of a cobbled-together Vacuum extractor.
After the baby is apparently stillborn, Rancho resuscitates it. ViruS reconciles with Rancho and his friends and allows them to take their final exams and they graduate. Rancho comes first and is awarded ViruS's pen, which the professor had been keeping for decades before finding a brilliant enough student to gift it to.
Their story is framed as intermittent flashbacks from the present day, ten years after Chatur vowed revenge on Rancho for embarrassing him at the speech night and promised to become more successful than Rancho a decade later. Having lost contact with Rancho, who disappeared during the graduation party and went into seclusion, Raju and Farhan begin a journey to find him. They are joined by Chatur, now a wealthy and successful businessman, who joins them, brazenly confident that he has surpassed Rancho. Chatur is also looking to seal a deal with a famous scientist and prospective business associate named Phunsukh Wangdu. Chatur sees Wangdu, who has hundreds of patents, as his ticket to further social prestige. When they find Rancho's house, they walk into his father's funeral, and find a completely different Rancho Jaaved Jaffrey. After accusing the new man of stealing their friend's identity and profiting from his intellect, the host pulls a gun on them, but Farhan and Raju turn the tables by seizing the father's ashes and threatening to flush them down the toilet. The householder capitulates and says that their friend was a destitute servant boy who loved learning, while he, the real Rancho, was a lazy wealthy child who disliked study, so the family agreed to let the servant boy study in Rancho's place instead of labouring. In return, the real Rancho would pocket the qualifications and the benefits thereof, while the impersonator would sever all contact with the world and start a new life. The real Rancho reveals that his impersonator is now a schoolteacher in Ladakh.
Raju and Farhan then find Pia, and take her from her wedding day to Suhas by performing the same tricks with his material possessions, and having Raju turn up to the ceremony disguised as the groom and eloping with Pia in public. When they arrive in Ladakh, they see a group of enthusiastic Ladakhi children who are motivated by love of knowledge. Pia and the fake Rancho rekindle their love, while Chatur mocks and abuses Rancho the schoolteacher before walking away. When his friends ask what his real name is, he reveals that it Phunsukh Wangdu and phones Chatur, who has turned his back, to turn around and meet his prospective business partner. Chatur is horrified and falls to his knees, accepts his defeat and continues to plead his case with Phunsukh to establish the business relationship he was after.
Threatened by Rancho's talent and free spirit, ViruS labels him an "idiot" and attempts on a number of occasions to destroy his friendship with Farhan and Raju, warning them and their parents to steer clear of Rancho. In contrast, ViruS model student is Chatur Ramalingam or "Silencer", (Omi Vaidya) who sees a high rank at the prestigious college as his ticket to higher social status, corporate power, and therefore wealth. Chatur conforms to the expectations of the system. Rancho humiliates Chatur, who is awarded the honour of making a speech at an award ceremony, by substituting obscenities into the text, which has been written by the librarian. As expected, Chatur mindlessly memorises the speech, without noticing that anything is amiss, partly aided by his lack of knowledge on Hindi. His speech becomes the laughing stock of the audience, infuriating the authorities in the process.
Meanwhile, Rancho also falls in love with ViruS' medical student daughter Pia (Kareena Kapoor) when he, Raju and Farhan crash her sister's wedding banquet in order to get a free meal, in the process further infuriating ViruS.
Meanwhile, the three students continue to anger ViruS, although Rancho continues to come first in every exam, while Chatur is always second, and Farhan and Raju are inevitably in the last two positions. The tensions come to a head when the three friends, who are already drunk, break into ViruS's house at night to allow Rancho to propose to Pia, and then urinate on a door inside the compound before running away when ViruS senses intruders. The next day, ViruS threatens to expel Raju lest he talks on the other two. Unable to choose between betraying his friend or letting down his family, Raju jumps out of the 3rd floor window and lands on a courtyard, but after extensive care from Pia and his roommates, awakes from a coma.
The experience has changed Farhan and Raju, and they adopt Rancho's outlook. Farhan decides to pursue his love of photography, while Raju takes an unexpected approach for an interview for a corporate job. He attends in plaster and a wheelchair and gives a series of non-conformal and frank answers. However, ViruS is unsympathetic and vows to make the final exam as hard as possible so that Raju is unable to graduate. Pia hears him and angrily confronts him, and when ViruS gives the same ruthless reply he gives to his students, she denounces him in the same way that Rancho did over the suicide of Lobo. Pia reveals that Viru's son and her brother was not killed in an accident but committed suicide in front of a train and left a letter because ViruS had forced him to pursue a career in engineering over his love for literature; ViruS always mentioned that he unsympathetically failed his son on the ICE entrance exams over and over to every new intake of ICE students. After this, Pia walks out on the family home, and takes ViruS's spare keys with her. She tells Rancho of the exam, and he and Farhan break into ViruS's office and steals the exam and give it to Raju, who with his new-found attitude, is unconcerned with the prospect of failing, and refuses to cheat and throws the paper away. However, ViruS catches the trio and expels them on the spot. However, they earn a reprieve when Viru's pregnant elder daughter Mona (Mona Singh) goes into labour at the same time. A heavy storm cuts all power and traffic, and Pia is still in self-imposed exile, so she instructs Rancho to deliver the baby in the college common room via VOIP, after Rancho restores power using car batteries and a power inverter that Rancho had dreamed up and ViruS had mocked. Rancho then delivers the baby with the help of a cobbled-together Vacuum extractor.
After the baby is apparently stillborn, Rancho resuscitates it. ViruS reconciles with Rancho and his friends and allows them to take their final exams and they graduate. Rancho comes first and is awarded ViruS's pen, which the professor had been keeping for decades before finding a brilliant enough student to gift it to.
Their story is framed as intermittent flashbacks from the present day, ten years after Chatur vowed revenge on Rancho for embarrassing him at the speech night and promised to become more successful than Rancho a decade later. Having lost contact with Rancho, who disappeared during the graduation party and went into seclusion, Raju and Farhan begin a journey to find him. They are joined by Chatur, now a wealthy and successful businessman, who joins them, brazenly confident that he has surpassed Rancho. Chatur is also looking to seal a deal with a famous scientist and prospective business associate named Phunsukh Wangdu. Chatur sees Wangdu, who has hundreds of patents, as his ticket to further social prestige. When they find Rancho's house, they walk into his father's funeral, and find a completely different Rancho Jaaved Jaffrey. After accusing the new man of stealing their friend's identity and profiting from his intellect, the host pulls a gun on them, but Farhan and Raju turn the tables by seizing the father's ashes and threatening to flush them down the toilet. The householder capitulates and says that their friend was a destitute servant boy who loved learning, while he, the real Rancho, was a lazy wealthy child who disliked study, so the family agreed to let the servant boy study in Rancho's place instead of labouring. In return, the real Rancho would pocket the qualifications and the benefits thereof, while the impersonator would sever all contact with the world and start a new life. The real Rancho reveals that his impersonator is now a schoolteacher in Ladakh.
Raju and Farhan then find Pia, and take her from her wedding day to Suhas by performing the same tricks with his material possessions, and having Raju turn up to the ceremony disguised as the groom and eloping with Pia in public. When they arrive in Ladakh, they see a group of enthusiastic Ladakhi children who are motivated by love of knowledge. Pia and the fake Rancho rekindle their love, while Chatur mocks and abuses Rancho the schoolteacher before walking away. When his friends ask what his real name is, he reveals that it Phunsukh Wangdu and phones Chatur, who has turned his back, to turn around and meet his prospective business partner. Chatur is horrified and falls to his knees, accepts his defeat and continues to plead his case with Phunsukh to establish the business relationship he was after.
Martes, Hulyo 26, 2011
Types of computers
Different types of Computers
Based on the operational principle of computers, they are categorized as analog computers and hybrid computers.
Analog Computers: These are almost extinct today. These are different from a digital computer because an analog computer can perform several mathematical operations simultaneously. It uses continuous variables for mathematical operations and utilizes mechanical or electrical energy.
Hybrid Computers: These computers are a combination of both digital and analog computers. In this type of computers, the digital segments perform process control by conversion of analog signals to digital ones.
Following are some of the other important types of computers.
Mainframe Computers: Large organizations use mainframes for highly critical applications such as bulk data processing and ERP. Most of the mainframe computers have the capacities to host multiple operating systems and operate as a number of virtual machines and can thus substitute for several small servers.
Microcomputers: A computer with a microprocessor and its central processing unit is known as a microcomputer. They do not occupy space as much as mainframes. When supplemented with a keyboard and a mouse, microcomputers can be called as personal computers. A monitor, a keyboard and other similar input output devices, computer memory in the form of RAM and a power supply unit come packaged in a microcomputer. These computers can fit on desks or tables and serve as the best choices for single-user tasks.
Personal computers come in a variety of forms such as desktops, laptops and personal digital assistants. Let us look at each of these types of computers.
Desktops: A desktop is intended to be used on a single location. The spare parts of a desktop computer are readily available at relative lower costs. Power consumption is not as critical as that in laptops. Desktops are widely popular for daily use in workplaces and households.
Laptops: Similar in operation to desktops, laptop computers are miniaturized and optimized for mobile use. Laptops run on a single battery or an external adapter that charges the computer batteries. They are enabled with an inbuilt keyboard, touch pad acting as a mouse and a liquid crystal display. Its portability and capacity to operate on battery power have served as a boon for mobile users.
Personal Digital Assistants (PDAs): It is a handheld computer and popularly known as a palmtop. It has a touch screen and a memory card for storage of data. PDAs can also be effectively used as portable audio players, web browsers and smart phones. Most of them can access the Internet by means of Bluetooth or Wi-Fi communication.
Minicomputers: In terms of size and processing capacity, minicomputers lie in between mainframes and microcomputers. Minicomputers are also called mid-range systems or workstations. The term began to be popularly used in the 1960s to refer to relatively smaller third generation computers. They took up the space that would be needed for a refrigerator or two and used transistor and core memory technologies. The 12-bit PDP-8 minicomputer of the Digital Equipment Corporation was the first successful minicomputer.
Supercomputers: The highly calculation-intensive tasks can be effectively performed by means of supercomputers. Quantum physics, mechanics, weather forecasting, molecular theory are best studied by means of supercomputers. Their ability of parallel processing and their well-designed memory hierarchy give the supercomputers, large transaction processing powers.
Wearable Computers: A record-setting step in the evolution of computers was the creation of wearable computers. These computers can be worn on the body and are often used in the study of behavior modeling and human health. Military and health professionals have incorporated wearable computers into their daily routine, as a part of such studies. When the users’ hands and sensory organs are engaged in other activities, wearable computers are of great help in tracking human actions. Wearable computers are consistently in operation as they do not have to be turned on and off and are constantly interacting with the user.
These were some of the different types of computers available today. Looking at the rate of the advancement in technology, we can definitely look forward to many more types of computers in the near future.
Based on the operational principle of computers, they are categorized as analog computers and hybrid computers.
Analog Computers: These are almost extinct today. These are different from a digital computer because an analog computer can perform several mathematical operations simultaneously. It uses continuous variables for mathematical operations and utilizes mechanical or electrical energy.
Hybrid Computers: These computers are a combination of both digital and analog computers. In this type of computers, the digital segments perform process control by conversion of analog signals to digital ones.
Following are some of the other important types of computers.
Mainframe Computers: Large organizations use mainframes for highly critical applications such as bulk data processing and ERP. Most of the mainframe computers have the capacities to host multiple operating systems and operate as a number of virtual machines and can thus substitute for several small servers.
Microcomputers: A computer with a microprocessor and its central processing unit is known as a microcomputer. They do not occupy space as much as mainframes. When supplemented with a keyboard and a mouse, microcomputers can be called as personal computers. A monitor, a keyboard and other similar input output devices, computer memory in the form of RAM and a power supply unit come packaged in a microcomputer. These computers can fit on desks or tables and serve as the best choices for single-user tasks.
Personal computers come in a variety of forms such as desktops, laptops and personal digital assistants. Let us look at each of these types of computers.
Desktops: A desktop is intended to be used on a single location. The spare parts of a desktop computer are readily available at relative lower costs. Power consumption is not as critical as that in laptops. Desktops are widely popular for daily use in workplaces and households.
Laptops: Similar in operation to desktops, laptop computers are miniaturized and optimized for mobile use. Laptops run on a single battery or an external adapter that charges the computer batteries. They are enabled with an inbuilt keyboard, touch pad acting as a mouse and a liquid crystal display. Its portability and capacity to operate on battery power have served as a boon for mobile users.
Personal Digital Assistants (PDAs): It is a handheld computer and popularly known as a palmtop. It has a touch screen and a memory card for storage of data. PDAs can also be effectively used as portable audio players, web browsers and smart phones. Most of them can access the Internet by means of Bluetooth or Wi-Fi communication.
Minicomputers: In terms of size and processing capacity, minicomputers lie in between mainframes and microcomputers. Minicomputers are also called mid-range systems or workstations. The term began to be popularly used in the 1960s to refer to relatively smaller third generation computers. They took up the space that would be needed for a refrigerator or two and used transistor and core memory technologies. The 12-bit PDP-8 minicomputer of the Digital Equipment Corporation was the first successful minicomputer.
Supercomputers: The highly calculation-intensive tasks can be effectively performed by means of supercomputers. Quantum physics, mechanics, weather forecasting, molecular theory are best studied by means of supercomputers. Their ability of parallel processing and their well-designed memory hierarchy give the supercomputers, large transaction processing powers.
Wearable Computers: A record-setting step in the evolution of computers was the creation of wearable computers. These computers can be worn on the body and are often used in the study of behavior modeling and human health. Military and health professionals have incorporated wearable computers into their daily routine, as a part of such studies. When the users’ hands and sensory organs are engaged in other activities, wearable computers are of great help in tracking human actions. Wearable computers are consistently in operation as they do not have to be turned on and off and are constantly interacting with the user.
These were some of the different types of computers available today. Looking at the rate of the advancement in technology, we can definitely look forward to many more types of computers in the near future.
COMPUTER
The earliest known device to record computations was the abacus. It dates back to ancient times and was invented by the Chinese. Ten beads were strung onto wires attached to a frame. Addition and subtraction were read from the final positions of the beads. It was considered the first manual tool used in calculating answers to problems that provided information and in a primitive way storing the results.
Mechanical ClockDuring the Middle Ages the first closed system in terms of calculating information was invented by use of a mechanical clock. The parts of the clock calculated the time of day. The time was displayed through the position of two hands on its face. The inventor pre-programmed the clock instructions through the manner in which the pull of the weights and the swing of the pendulum with the movement of the gears established the position of the hands on the clock face.
MathematicsJohn Napier (Scotsman mid 1600s) discovered logarithms. He devised a system where he put the logarithms on a set of ivory rods called "Napier’s Bones". By sliding the numbers up and down he invented a very primitive slide rule. Robert Bissaker perfected the system by placing numbers on sliding pieces of wood rather than ivory.
Blaise Pascal(1642) developed the first real calculator. Addition and subtraction were carried out by using a series of very light rotating wheels. His system is still used today in car odometers which track a car’s mileage.
Gottfried van Leibnitz(German mathematician) In 1690 Leibnitz developed a machine that could add, subtract, multiply, divide, and calculate square roots. The instructions were programmed into the machine. Programming was accomplished through the use of gears. The drawback to this machine was that the instructions could not be changed without changing the whole machine.
Joseph Jacquard(early 1800’s) Jacquard developed a loom controlled by punched cards. The cards were made of cardboard which were programmed with instructions. Each card represented a loop, and the machine read the cards as they were passed over a series of rods. The loom was the early ancestor of the IBM punched card.
Charles Babbage(1812) Babbage was a genius of a man who saw few of his inventions actually built. He designed and built a model of what was called the difference engine. This invention was designed to perform calculations without human intervention. The ultimate goal of the machine was to have the machine calculate logarithm tables and print the results. Babbage was so far ahead of the times that the technology was not in place to manufacture the parts for his machine so he was only able to build a small model. In 1833, Babbage then designed the analytic engine. This machine had many of the same parts that could be found in modern day computers. It had an arthmetic unit which performed calculations. Another part of the computer was called the "store" which stored intermediate and final results and instructions. This was completed for each stage of calculation. It was to get its instructions from punched cards and worked through mechanical means. The machine would be able to perform any calculation. Before the machine could be made Babbage died. His son built a small model of the work that still exists today. Babbage became known as the father of the modern day computers.
Dr. Herman Hollerith(late 1800 statistician) Hollerith used the punched card method to process data gathered in the census. The previous census had taken seven years to complete because of the large amount of data collected that needed to be processed. By developing the Hollerith code and a series of machines which could store census data on cards, he was able to accomplish the accounting of the census in two and a half years with an additional two million pieces of data added. His code was able to sort the data according to the needs of the United States Government. He was known for developing the first computer card and accomplishing the largest data processing endeavor undertaken at the time. Hollerith set up the Tabulating Machine Company which manufactured and marketed punched cards and equipment to the railroads. The railroads used the equipment to tabulate freight schedules. In 1911, the Tabulating Machine Company merged with other companies to form the International Business Machine Corporation (IBM).
William Burroughs
(late 1890’s) designed the mechanical adding machine. The machine operated by way of a crank and was key driven. The Burroughs Adding Machine Company was to become one of the giants of the computer industry. His machine could record, calculate, and summarize. Today, Burroughs has merged with UNISYS which builds computers.
The Years from 1900-1940During the next forty years, more of the adding, calculating, and tabulating machines were developed. Eventually the machines evolved to a point where they could multiply, interpret the alphabetic data, recordkeeping, and other accounting functions. They were called accounting machines.
Howard Aiken(1944) The Mark I ,through a collaboration with Harvard University, IBM, and the U.S. War Department, was developed to handle a large amount of number crunching. The complex equation solving that was needed to map logistics in the military was the driving force behind this project. ( The United States was at war with Germany.) The Mark I was the first automatic calculator. It was not electronic, but did use electromagnetic relays with mechanical counters. It was said that when it ran the clicking sound was unbearable. Paper tape with hole punched in it provided the instruction sets, and the output was returned through holes punched in cards.
J. Presper Eckert and John W. Mauchly(ENIAC, 1946 University of Pennsylvania) The ENIAC (Electronic Numerical Integrator and Calculator) was an electronic computer sponsored by the war department. It was classified because of war purposes. The ENIAC was so large that it took up a room ten feet high by about ten feet wide and several hundred feet in length. It could perform multiplication in the 3/1000 of a second range. There were 18,000 vacuum tubes in the machine and instructions had to be fed into the machine by way of switches because there was no internal memory within the machine.
Jon Von Neumann(late 1940’s) devised a way to encode instructions and data in the same language. This paved the way for computer instructions to be stored in the computer itself. He was the forced behind the development of the first stored-program computer.
A Race Between the EDVAC and the EDSAC
Two groups of individuals were working at the same time to develop the first stored-program computer. In the United States, at the University of Pennsylvania the EDVAC (Electronic Discrete Variable Automatic Computer) was being worked on. In England at Cambridge, the EDSAC (Electronic Delay Storage Automatic Computer) was also being developed. The EDSAC won the race as the first stored-program computer beating the United States’ EDVAC by two months. The EDSAC performed computations in the three millisecond range. It performed arithmetic and logical operations without human intervention. The key to the success was in the stored instructions which it depended upon solely for its operation. This machine marked the beginning of the computer age.
(1951) The first generation of computers started with the UNIVAC I (Universal Automatic Computer) built by Mauchly and Eckert. It was sold to the U.S. Census Bureau. This machine was dedicated to business data processing and not military or scientific purposes.
Characteristics of First Generation ComputersUse of vacuum tubes in electronic circuits: These tubes controlled internal operations and were huge. As a consequence the machines were large.
Magnetic drumas primary internal-storage medium: Electric currents passed through wires which magnetized the core to represent on and off states
Limited main-storage capacity:Slow input/output, punched-card-oriented: Operators performed input and output operations through the use of punched cards.
Low level symbolic-language programming: The computer used machine language which was cumbersome and accomplished through long strings of numbers made up of Zeroes and Ones. In 1952, Dr. Grace Hopper (University of Pennsylvania) developed a symbolic language called mnemonics (instructions written with symbolic codes). Rather than writing instructions with Zeroes and Ones, the mnemonics were translated into binary code. Dr. Hopper developed the first set of programs or instructions to tell computers how to translate the mnemonics.
Heat and maintenance problems: Special air-conditioning and maintenance were required of the machines. The tubes gave off tremendous amounts of heat.
Applications: payroll processing and record keeping though still oriented toward scientific applications thatn business data processing.
Examples: IBM 650 UNIVAC I
Magnetic core and solid-state main storage: Greater storage capacity was developed.
More flexibility with input/output; disk-oriented:
Smaller size and better performance and reliability: Advances in solid-state technology allowed for the design and building of smaller and faster computers. Breadboards could easily be replaced on the fly.
Extensive use of high-level programming languages: The software industry evolved during this time. Many users found that it was more cost effective to buy pre-programmed packages than to write the programs themselves. The programs from the second generation had to be rewritten since many of the programs were based on second generation architecture.
Emergence of minicomputers: The mini computers offered many of the same features as the mainframe computers only on a smaller scale. These machines filled the needs of the small business owner.
Remote processing and time-sharing through communication: Computers were then able to perform several operations at the same time. Remote terminals were developed to communicate with a central computer over a specific geographic location. Time sharing environments were established.
Availability of operating-systems(software) to control I/O and do tasks handled by human operators: Software was developed to take care of routine tasks required of the computer freed up the human operator.
Applications such as airline reservation systems, market forcasting, credit card billing: The applications also included inventory, control, and scheduling labor and materials. Multitasking was also accomplished. Both scientific and business applications could be run on the same machine.
Examples: IBM System/360 NCR 395 Burroughs B6500
Increased storage capacity and speed.
Modular design and compatibility between equipment
Special application programs
Versatility of input/ output devices
Increased use of minicomputers
Introduction of microprocessors and microcomputers
Applications: mathematical modeling and simulation, electronic funds transfer, computer-aided instruction and home computers. Internet Explosion.
History of the Internet
The ARPANET evolved from a series of research experiments begun in late 1960s. (The premise for this researchwas a fear that a thermonuclear strike might knock out the military’s ability to communicate with its troops). The Department of Defense funded research on computer networking.The research was used to try and improve military communications.The project was called the Advanced Research Projects Administration (ARPA). A wide based area network called ARPANET resulted.)
Networks were very fragile. Just one computer being down would cause the whole network to come down. To provide better defense, the computers were kept decentralized, so that no main computer could be disabled. Inorder to make this happen, a computer protocol called Transmission Control Protocol (TCP/IP) was created. The protocol worked in a manner in which if information could not get to its destination through one route, then it would automatically be rerouted through another route.
How does this work? The communication is only between the computer sending the information and the computer receiving the information . The information required by the computers is very little. The network does not take care of the communication. It only provides the line or pipeline for information. The sending computer puts information in a packet.
The packet is enclosed in an Internet Protocol (IP) packet and adds the address to the receiving computer. All computers on the network are equal, no matter what the platform.
By 1980 ARPANET became the prototype Internet. There were 200 computers on the net. The Computer Science Network (CSNET) funded by the National Science Foundation (NSF) was then added to ARPANET. By 1983, the defense department used this combined network as its primary communications network. The number of computers connected at that time then rose to 562. In 1984, a total of 1,024 computers were connected.
In 1985, NSFNET a new network was created by the National Science Foundation. It was created to link five supercomputer centers across the country. The ARPANET was then hooked up to it, using the same protocols. The net only lasted until 1986, because the network capacity was not large enough to hold both groups. THE ARPANET was shut down very quietly and no one even noticed since the Internet was a network of networks.
In 1987 Merit Network Inc. was given a contract to manage an upgrade a new network. The National Science Foundation helped with the funding to install a high speed network that used 56,000 bit per second (56 Kbps) telephone lines. This occurred in 1988. In 1988, 28,174 computers were on the Internet. In 1989 there were 80,000. In 1990- 290,000 computers were using the Internet.
Mechanical ClockDuring the Middle Ages the first closed system in terms of calculating information was invented by use of a mechanical clock. The parts of the clock calculated the time of day. The time was displayed through the position of two hands on its face. The inventor pre-programmed the clock instructions through the manner in which the pull of the weights and the swing of the pendulum with the movement of the gears established the position of the hands on the clock face.
MathematicsJohn Napier (Scotsman mid 1600s) discovered logarithms. He devised a system where he put the logarithms on a set of ivory rods called "Napier’s Bones". By sliding the numbers up and down he invented a very primitive slide rule. Robert Bissaker perfected the system by placing numbers on sliding pieces of wood rather than ivory.
Blaise Pascal(1642) developed the first real calculator. Addition and subtraction were carried out by using a series of very light rotating wheels. His system is still used today in car odometers which track a car’s mileage.
Gottfried van Leibnitz(German mathematician) In 1690 Leibnitz developed a machine that could add, subtract, multiply, divide, and calculate square roots. The instructions were programmed into the machine. Programming was accomplished through the use of gears. The drawback to this machine was that the instructions could not be changed without changing the whole machine.
Joseph Jacquard(early 1800’s) Jacquard developed a loom controlled by punched cards. The cards were made of cardboard which were programmed with instructions. Each card represented a loop, and the machine read the cards as they were passed over a series of rods. The loom was the early ancestor of the IBM punched card.
Charles Babbage(1812) Babbage was a genius of a man who saw few of his inventions actually built. He designed and built a model of what was called the difference engine. This invention was designed to perform calculations without human intervention. The ultimate goal of the machine was to have the machine calculate logarithm tables and print the results. Babbage was so far ahead of the times that the technology was not in place to manufacture the parts for his machine so he was only able to build a small model. In 1833, Babbage then designed the analytic engine. This machine had many of the same parts that could be found in modern day computers. It had an arthmetic unit which performed calculations. Another part of the computer was called the "store" which stored intermediate and final results and instructions. This was completed for each stage of calculation. It was to get its instructions from punched cards and worked through mechanical means. The machine would be able to perform any calculation. Before the machine could be made Babbage died. His son built a small model of the work that still exists today. Babbage became known as the father of the modern day computers.
Dr. Herman Hollerith(late 1800 statistician) Hollerith used the punched card method to process data gathered in the census. The previous census had taken seven years to complete because of the large amount of data collected that needed to be processed. By developing the Hollerith code and a series of machines which could store census data on cards, he was able to accomplish the accounting of the census in two and a half years with an additional two million pieces of data added. His code was able to sort the data according to the needs of the United States Government. He was known for developing the first computer card and accomplishing the largest data processing endeavor undertaken at the time. Hollerith set up the Tabulating Machine Company which manufactured and marketed punched cards and equipment to the railroads. The railroads used the equipment to tabulate freight schedules. In 1911, the Tabulating Machine Company merged with other companies to form the International Business Machine Corporation (IBM).
William Burroughs
(late 1890’s) designed the mechanical adding machine. The machine operated by way of a crank and was key driven. The Burroughs Adding Machine Company was to become one of the giants of the computer industry. His machine could record, calculate, and summarize. Today, Burroughs has merged with UNISYS which builds computers.
The Years from 1900-1940During the next forty years, more of the adding, calculating, and tabulating machines were developed. Eventually the machines evolved to a point where they could multiply, interpret the alphabetic data, recordkeeping, and other accounting functions. They were called accounting machines.
Howard Aiken(1944) The Mark I ,through a collaboration with Harvard University, IBM, and the U.S. War Department, was developed to handle a large amount of number crunching. The complex equation solving that was needed to map logistics in the military was the driving force behind this project. ( The United States was at war with Germany.) The Mark I was the first automatic calculator. It was not electronic, but did use electromagnetic relays with mechanical counters. It was said that when it ran the clicking sound was unbearable. Paper tape with hole punched in it provided the instruction sets, and the output was returned through holes punched in cards.
J. Presper Eckert and John W. Mauchly(ENIAC, 1946 University of Pennsylvania) The ENIAC (Electronic Numerical Integrator and Calculator) was an electronic computer sponsored by the war department. It was classified because of war purposes. The ENIAC was so large that it took up a room ten feet high by about ten feet wide and several hundred feet in length. It could perform multiplication in the 3/1000 of a second range. There were 18,000 vacuum tubes in the machine and instructions had to be fed into the machine by way of switches because there was no internal memory within the machine.
Jon Von Neumann(late 1940’s) devised a way to encode instructions and data in the same language. This paved the way for computer instructions to be stored in the computer itself. He was the forced behind the development of the first stored-program computer.
A Race Between the EDVAC and the EDSAC
Two groups of individuals were working at the same time to develop the first stored-program computer. In the United States, at the University of Pennsylvania the EDVAC (Electronic Discrete Variable Automatic Computer) was being worked on. In England at Cambridge, the EDSAC (Electronic Delay Storage Automatic Computer) was also being developed. The EDSAC won the race as the first stored-program computer beating the United States’ EDVAC by two months. The EDSAC performed computations in the three millisecond range. It performed arithmetic and logical operations without human intervention. The key to the success was in the stored instructions which it depended upon solely for its operation. This machine marked the beginning of the computer age.
First Generation (1951-1958)
John W. Mauchly and J. Presper Eckert(1951) The first generation of computers started with the UNIVAC I (Universal Automatic Computer) built by Mauchly and Eckert. It was sold to the U.S. Census Bureau. This machine was dedicated to business data processing and not military or scientific purposes.
Characteristics of First Generation ComputersUse of vacuum tubes in electronic circuits: These tubes controlled internal operations and were huge. As a consequence the machines were large.
Magnetic drumas primary internal-storage medium: Electric currents passed through wires which magnetized the core to represent on and off states
Limited main-storage capacity:Slow input/output, punched-card-oriented: Operators performed input and output operations through the use of punched cards.
Low level symbolic-language programming: The computer used machine language which was cumbersome and accomplished through long strings of numbers made up of Zeroes and Ones. In 1952, Dr. Grace Hopper (University of Pennsylvania) developed a symbolic language called mnemonics (instructions written with symbolic codes). Rather than writing instructions with Zeroes and Ones, the mnemonics were translated into binary code. Dr. Hopper developed the first set of programs or instructions to tell computers how to translate the mnemonics.
Heat and maintenance problems: Special air-conditioning and maintenance were required of the machines. The tubes gave off tremendous amounts of heat.
Applications: payroll processing and record keeping though still oriented toward scientific applications thatn business data processing.
Examples: IBM 650 UNIVAC I
Second Generation Computers (1959-1964)
Characteristics of Second Generation Computers
Use of transitors for internal operations: tiny solid state transitors replace vacuum tubes in computers. The heat problem was then minimized and computers could be made smaller and faster.
Magnetic core as primary internal-storage medium: Electric currents pass through wires which magnetize the core to represent on and off states.Data in the cores can be found and retrieved for processing in a few millionths of a second.
Increased main-storage capacity: The internal or main storage was supplemented by use of magnetic tapes for external storage. These tapes substituted for punched cards or paper. Magnetic disks were also developed that stored information on circular tracks that looked like phonograph records. The disks provided direct or random access to records in a file.
Faster input/output; tape orientation: Devices could be connected directly to the computer and considered "on-line". This allowed for faster printing and detection and correction of errors.
High-level programming languages (COBOL,FORTRAN) : These languages resembled English. FORTRAN (FORmula TRANslator) was the first high-level language that was accepted widely. This language was used mostly for scientific applications. COBOL (Common Business-Oriented Language) was developed in 1961 for business data processing. Its main features include: file-processing, editing, and input/output capabilites.
Increased speed and reliability: Modular-hardware was developed through the design of electronic circuits. Complete modules called "breadboards" could be replaced if malfunctions occurred, or the machine "crashed". This decreased lost time and also new modules could be added for added features such as file-processing, editing , and input/output features.
Batch-oriented applications:billing, payroll processing, updating and inventory files: Batch processing allowed for collection of data over a period time and then one processed in one computer run. The results were then stored on magnetic tapes.
Examples:IBM 1401*(most popular business-oriented computer. Honeywell 200 CDC 1604
Third Generation Computers (1965-1970)
Characteristics of Third Generation Computers:Use of integrated circuits: The use of integrated circuits (Ics) replaced the transitors of the second-generation machines. The circuits are etched and printed and hundreds of electronic components could be put on silicon circuit chips less than one-eighth of an inch square.Magnetic core and solid-state main storage: Greater storage capacity was developed.
More flexibility with input/output; disk-oriented:
Smaller size and better performance and reliability: Advances in solid-state technology allowed for the design and building of smaller and faster computers. Breadboards could easily be replaced on the fly.
Extensive use of high-level programming languages: The software industry evolved during this time. Many users found that it was more cost effective to buy pre-programmed packages than to write the programs themselves. The programs from the second generation had to be rewritten since many of the programs were based on second generation architecture.
Emergence of minicomputers: The mini computers offered many of the same features as the mainframe computers only on a smaller scale. These machines filled the needs of the small business owner.
Remote processing and time-sharing through communication: Computers were then able to perform several operations at the same time. Remote terminals were developed to communicate with a central computer over a specific geographic location. Time sharing environments were established.
Availability of operating-systems(software) to control I/O and do tasks handled by human operators: Software was developed to take care of routine tasks required of the computer freed up the human operator.
Applications such as airline reservation systems, market forcasting, credit card billing: The applications also included inventory, control, and scheduling labor and materials. Multitasking was also accomplished. Both scientific and business applications could be run on the same machine.
Examples: IBM System/360 NCR 395 Burroughs B6500
Fourth Generation (1970-)
Characteristics of Fourth Generation Computers:Use of large scale integrated circuitsIncreased storage capacity and speed.
Modular design and compatibility between equipment
Special application programs
Versatility of input/ output devices
Increased use of minicomputers
Introduction of microprocessors and microcomputers
Applications: mathematical modeling and simulation, electronic funds transfer, computer-aided instruction and home computers. Internet Explosion.
- Control Data Corporation: STAR 100 computer which has a vector based design. Information is processed as vectors instead of numbers. This allows for faster speed when problems are processed in vector form. Charles A. Burrus develops the (LED) light-emitting diode. RCA develops (MOS) technology, a metal-oxide semiconductor for the making of integrated circuits, making them cheaper and faster to produce. The circuits can also be made smaller.
- Texas Instruments introduces the first pocket calculator the Pocketronic. It can add subtract, multiply and divide. It costs around $150.
- Odyssey developed by Magnavox(first video game).Intel develops the first 8-bit microprocessor chip the 8008. (Used in the Mark-8 personal mini-computer). Nolan Bushnell invents a video game with a liquid crystal screen. The toy is called Pong. Bushnell founds Atari.
- Using LSI (large scale integration) ten thousand components are placed on a chip of 1 square inch.
- Hewlett Packard introduces the programmable pocket calculator. David Ahl develops a microcomputer consisting of a video display, keyboard and central processing unit. D-RAM (dynamic random access becomes commercially available and will be used in the first personal computers.
- Edward Roberts introduces the first personal computer call the Altair 8800 in kit form. It has 256 bytes of memory.
- A computer chip with 16 kilobits (16,384 bits) of memory becomes commercially available. It will be used in the first IBM personal computer.
- Steve P. Jobs and Stephen Wozniak introduce the Apple II. The first personal computer in assembled form. Xerox introduces the Star 8010 and office computer based on the Alto developed a few years earlier. The first linked automatic teller machines (ATMs) are introduced in Denver.
- DEC introduces a 32-bit computer with a virtual address extension (VAX). It runs large programs and becomes an industry standard for scientific and technical systems. Its operating system is called a VMS. Intel introduces its first 16-bit processor the 8086. The 8088 is used in the central processing unit in their first PC.
- Control Data introduces Cyber 203 supercomputer. Motorola introduces the 68000 microprocessor chip. It is a 24-bit capacity chip for reading memory and can address 16 megabytes of memory. It will be the basis for the Macintosh computer developed by Apple. Steven Hofstein invents the field-effect transistor using metal oxide technology. (MOSFET)1881 IBM Personal Computer uses the industry standard disk operating system. (DOS)
- IBM introduces the 5120 microcomputer. It is not successful.
- Osborne builds the first portable computer in which disk drives, monitor, and processor are mounted in a single box. It is the size of a suitcase. Clive Sinclair develops the ZX81 which connects to a television receiver. Japanese produce 64 kilobit chips (65,536 bits) of memory which captures the world market.
- Columbia Data Products announces the first computer based on the IBM PC that run programs designed for the IBM machine and gets the name "clones". Compaq introduces its first IBM-PC clone that is portable. Japan starts a project nationally funded to develop a fifth generation computer based on artificial intelligence using the Prolog language.
- IBM’s PC-XT introduced. It is the first personal computer with a hard drive built into the computer. It can store 10 megabytes of information even when the machine is turned off. It replaces many floppy diskettes. The machine is updated using DOS 2.0. IBM introduces PC-JR a scaled down version of the IBM-PC. It is unsuccessful. Immos, (British company) develops a transputer which several processors are contained in one computer and they work simultaneously on the same problem. Intel introduces the 8080, and 8 bit microprocessor that replaces the 8008.
- Philips and Sony introduce the CD-ROM (compact disk ready-only memory) an optical disk that can store large amounts of information. Apple introduces the Macintosh, a graphics based computer that use icons, a mouse and an intuitive interface derived from the Lisa computer. IBM ‘s PC AT (advanced technology) computer designed around the 16 bit Intel 80286 processor chip and running at 6 MHz becomes the first personal computer to use a new chip to expand speed and memory. Motorola introduces the 68020 version of the 68000 series of microprocessors. It has a 32-bit processing and reading capacity. NEC manufactures computer chips in Japan with 256 kilobits (262,144) of computer memory. IBM introduces a megabit RAM (random access memory) chip with four times the memory of earlier chips.
- Microsoft develops Windows for the IBM-PC. Intel introduces the 80386, a 32-bit microprocessor. Masaki Togai and Hiroyuki Watanabe develop a logic chip that operates on fuzzy logic at Bell Labs.
- Compaq leaps past IBM by introducing the DeskPro, a computer that uses an advanced 32-bit microprocessor, the Intel 80386. It can run software faster than the quickest 16-bit computer. Terry Sejnowski at Johns Hopkins in Baltimore develops a neural network computer that can read text out loud without knowing any pronunciation rules. The first DAT (digital audio tape) recorders are developed in Japan.
- The Macintosh II and Macintosh SE made by Apple become the most powerful personal computers.Sega Electronics introduces a three dimensional video game. The images appear three-dimensional. Telephones become available on commercial airplanes. Computer chips are manufactured with a 1 megabyte (1000 kilobits or 1,048,576 bits) of computer memory. Japan also introduces an experimental 4 and 16 megabit chip.
- Motorola introduces it 32 bit 88000 series of RISC (reduced instruction set computing) microprocessors. They can operate much faster than conventional chips.Compaq and Tandy develop the EISA (Extended Industry Standard Architecture). Steven Jobs introduces the NeXT Computer System. It is a graphical-based system that includes 256 megabyte optical storage disk and 8 megabytes of RAM. Robert Morris develops a computer virus that is planted in the Internet and causes the whole system to go down for two days. Scriptel introduces a method for inputing data into a computer by writing on a screen.
- Japan initiates daily broadcasts of it analog version of high definition television. (HDTV). Philips and Sony bring the videodisk to the open market. Seymour Cray founds the Cray Computer Corporation.
- Bell Laboratories Alan Huang demonstrates the first all-optical processor. Hewlett Packard announces a computer with RISC processor. IBM later introduces the RS/6000 family of RISC workstations. Computer chips introduced with 4 megabit of computer memory. Intel introduces the i486 processor chip which can operate at 33 MHz. Intel also launches the iPSC/860 microprocessor that is designed for multiprocessor computers. Motorola introduces the 68040 version of its 68000 series of microprocessors. The chip has 1.2 million transistors. IBM develops a transistor that can operate at 75 billion cycles per second.
- The 64-megabyte dynamic random access memory chip is invented. (D-RAM)
- IBM develops the silicon insulator (SOI) bipolar transistor. It can operate at 20 GHz .
- Harry Jordan and Vincent Heuring develop the first general purpose-all optical computer capable of being programmed and manipulating instructions internally. Intel ships their Pentium processor to computer manufacturers. It is the fifth generation of the chip that powers the PC. The chip contains 3.1 million transistors and is twice a fast as the fourth generation 486DX2. Fujitsu in Japan announces of a 256 megabit memory chip.
History of the Internet
The ARPANET evolved from a series of research experiments begun in late 1960s. (The premise for this researchwas a fear that a thermonuclear strike might knock out the military’s ability to communicate with its troops). The Department of Defense funded research on computer networking.The research was used to try and improve military communications.The project was called the Advanced Research Projects Administration (ARPA). A wide based area network called ARPANET resulted.)
Networks were very fragile. Just one computer being down would cause the whole network to come down. To provide better defense, the computers were kept decentralized, so that no main computer could be disabled. Inorder to make this happen, a computer protocol called Transmission Control Protocol (TCP/IP) was created. The protocol worked in a manner in which if information could not get to its destination through one route, then it would automatically be rerouted through another route.
How does this work? The communication is only between the computer sending the information and the computer receiving the information . The information required by the computers is very little. The network does not take care of the communication. It only provides the line or pipeline for information. The sending computer puts information in a packet.
The packet is enclosed in an Internet Protocol (IP) packet and adds the address to the receiving computer. All computers on the network are equal, no matter what the platform.
By 1980 ARPANET became the prototype Internet. There were 200 computers on the net. The Computer Science Network (CSNET) funded by the National Science Foundation (NSF) was then added to ARPANET. By 1983, the defense department used this combined network as its primary communications network. The number of computers connected at that time then rose to 562. In 1984, a total of 1,024 computers were connected.
In 1985, NSFNET a new network was created by the National Science Foundation. It was created to link five supercomputer centers across the country. The ARPANET was then hooked up to it, using the same protocols. The net only lasted until 1986, because the network capacity was not large enough to hold both groups. THE ARPANET was shut down very quietly and no one even noticed since the Internet was a network of networks.
In 1987 Merit Network Inc. was given a contract to manage an upgrade a new network. The National Science Foundation helped with the funding to install a high speed network that used 56,000 bit per second (56 Kbps) telephone lines. This occurred in 1988. In 1988, 28,174 computers were on the Internet. In 1989 there were 80,000. In 1990- 290,000 computers were using the Internet.
Huwebes, Hulyo 21, 2011
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