History Of Computer

First Generation of Computer (1940-Early 1950s)

• By 1941 the German engineer Konrad Zuse had developed a computer, the Z3, to design airplanes and missiles. 
• In 1942 the British completed a secret code-breaking computer called Colossus to decode German messages
•  In the year 1943 the Electronic Numerical Integrator and Computer (ENIAC), a general-purpose computer, was produced by a partnership between the U.S. Government and the University of Pennsylvania consists of 18.000 vacuum tubes, 70.000 resistors and 5 million soldered joints, the computer was such a massive piece of machinery (floor space: 1,000 square feet) that it consumed 160 kilowatts of electrical power, enough energy to dim lights in an entire section of a bigger town.
• By 1945 the Hungarian-American mathematician John von Neumann created the Electronic Discrete Variable Automatic Computer (EDVAC) with a memory to hold both a stored program as well as data. The key element of the Neumann architecture was the central processing unit(CPU), which allowed all computer functions to be coordinated through a single source.
• The first generation computers used vacuum tubes for circuitry and magnetic drums for memory. 

Second Generation Computers Late 1950s - Early 1960s: Transistors

• Transistors replaced vacuum tubes and ushered in the second generation of computers. The transistor was invented in 1947 but did not see widespread use of computers until the late 1950s. This generation used ferrite cores for main memory and magnetic disk drum/tapes as secondary memory.
• IBM and LARC by Sperry-Rand (1959) were the first large-scale machines to take advantage of the transistor technology (and also used assembly language instead of the difficult machine language). 
• Second-generation computers moved from cryptic binary machine language to symbolic, or assembly, languages, which allowed programmers to specify instructions in words. High-level programming languages were also being developed at this time, such as early versions of COBOL (Common Business-Oriented Language), 1960, and FORTRAN (Formular Translator), 1956,. These were also the first computers that stored their instructions in their memory, which moved from a magnetic drum to magnetic core technology.
• Some  of  the  computers  in  this  generation  are  TX-0 (Transistorized  experimental Computer),  TX-2,  NEAC   1101  (from NEC),  PDP   series  computers  from  Digital
• Company, IBM series computers such as IBM 709, IBM 1400 series etc. CDC (Control  Data  Corporation)  built fast computers called supercomputers  -  CDC 6600. 

Third Generation of Computer (Late 1960s - Early 1970s):Integrated Circuits

• The invention of silicon ICs (Integrated Circuits) allowed dozens of transistors to be put on a single chip. They used magnetic disks as memory devices but later they were replaced by semiconductor memories. 
• The IBM 360 was introduced by IBM (duh!) in April of 1964, and was finally delivered in 1965. It was not actually a single computer, but was rather a family of six computers and their peripherals. The first models of the IBM 360 used transistors, but later these computers made a transition from transistors to integrated circuits. 
•  By the year 1965 PDP-8 was manufactured which was a successor to the PDP-1. This machine became the first commercially successful mini computer because of its reasonable cost, speed and small size.
• With the invention of the HP-2115 in 1966, the company Hewlett Packard enters the computer business.
• The operating systems like GUI (graphical user interface, pronounced gooey),by the Xerox Corporation, in the year 1970 and UNIX, by programmers Kenneth Thompson and Dennis Ritchie in the year 1969 were developed.

Fourth Generation (1971-Present) Microprocessors

• The microprocessor brought the fourth generation of computers, as thousands of integrated circuits were built onto a single silicon chip. What in the first generation filled an entire room could now fit in the palm of the hand. 
• The Intel 4004 chip, developed in 1971, located all the components of the computer—from the central processing unit and memory to input/output controls—on a single chip.
• In November of 1972, Intel came out with a new 8-bit processor, known as the Intel 8008.
• The Intel 8080 is a re-engineered version of the Intel 8008. It had a larger and more versatile instruction set.
• The Altair 8800 is often called the first personal computer. It was developed by Micro Instrumentation Telemetry Systems (MITS), a small company centered in Albuquerque, New Mexico in 1975.
• Developed in 1976 by Gary Kildall of the company Digital Research, CP/M was a popular operating system that made it possible for one version of a program to run on a variety of computers.
• Apple Computer was started by Stephen G. Wozniak and Steven P. Jobs. In 1976, the company introduced the Apple II to the personal computer market.
• VisiCalc, standing for Visible Calculator, is the first personal computer financial analysis tool. This software was developed by Harvard business graduate Dan Bricklin and programmer Bob Frankston. VisiCalc was able to give immediate responses to "what if" questions.
• Invented by Adam Osborne in 1981, the Osborne I was the world's first portable computer. 
• The Apple Macintosh was designed by Apple Computer  in the year 1984. It used the minimum number of chips and circuit boards needed to operate efficiently. It had graphical user interface and a user-friendly design. 
• In 1996, IBM invents a supercomputer named "Deep Blue." Able to compute more than 100 million chess positions per second.
• Fourth generation computers saw the development of GUIs, the mouse and handheld devices.

Fifth Generation (Present and Beyond) Artificial Intelligence

• Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice recognition, that are being used today. The use of parallel processing and superconductors is helping to make artificial intelligence a reality. Quantum computation and molecular and nanotechnology will radically change the face of computers in years to come. The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization.