THE COMPUTER AGES

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 Computers
Use of vacuum tubes in electronic circuits: These tubes controlled internal operations and were huge. As a consequence the machines were large.
Magnetic drum
as 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 circuits
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.
1970. 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.
1971. Texas Instruments introduces the first pocket calculator the Pocketronic. It can add subtract, multiply and divide. It costs around $150.
1972. 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.
1973. Using LSI (large scale integration) ten thousand components are placed on a chip of 1 square inch.
1974. 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.
1975. Edward Roberts introduces the first personal computer call the Altair 8800 in kit form. It has 256 bytes of memory.
1976. A computer chip with 16 kilobits (16,384 bits) of memory becomes commercially available. It will be used in the first IBM personal computer.
1977. 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.
1978. 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.
1979. 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)
1980. IBM introduces the 5120 microcomputer. It is not successful.
1981. 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.
1982. 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.
1983. 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.
1984. 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.
1985. 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.
1986. 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.
1987. 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.
1988. 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.
1989. 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.
1990. 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.
1991. The 64-megabyte dynamic random access memory chip is invented. (D-RAM)
1992. IBM develops the silicon insulator (SOI) bipolar transistor. It can operate at 20 GHz .
1993. 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.


1994 to the present. The world is changing rapidly and so is the explosion of information. The computer is an ever changing and evolving beast. Currently in 1998, the computers are at speeds of 400 MHz with harddrives averaging 6.4 gigabytes of memory. Components are becoming smaller and computers are becoming faster. Multimedia and webbased publishing are the current trends. There is a rush to incorporate networks and Internet access into the schools, and with the development of Internet II; virtual reality seems to becoming closer to a reality. Where will the future lead us next?