An inspiring summer school on computing at the University of Pennsylvania stimulated construction of stored-program computers such as the EDSAC at universities and research institutions.
IBM´s SSEC 1948
IBM´s Selective Sequence Electronic Calculator computed scientific data. Before its decommissioning in 1952, the SSEC produced the moon-position tables used for plotting the course of the 1969 Apollo flight to the moon.
50 multiplications per second
cards, punched tape
punched tape, vacuum tubes, relays
20,000 relays, 12,500 vacuum tubes
25 feet by 40 feet
Maurice Wilkes assembled the EDSAC, the first practical stored-program computer.
For programming the EDSAC, Wilkes established a library of short programs called subroutines stored on punched paper tapes.
1K words, 17 bits, mercury delay line
714 operations per second
Mark I 1949
The Manchester Mark I computer functioned as a complete system.
Start of project:
paper tape, teleprinter, switches
128 + 1024 40-digit words
cathode ray tube, magnetic drum
1,300 vacuum tubes
Frederick Williams and Tom Kilburn
ERA 1101 drum memory
The ERA 1101, the first commercially produced computer; was built for the U.S. Navy. It held 1 million bits on its magnetic drum, the earliest magnetic storage devices. Drums registered information as magnetic pulses in tracks around a metal cylinder. Read/write heads both recorded and recovered the data. Drums eventually stored as many as 4,000 words and retrieved any one of them in as little as five-thousandths of a second.
The SEAC was the first computer to use all-diode logic, a technology more reliable than vacuum tubes, and the first stored-program computer completed in the United States. Magnetic tape in the external storage units stored programming information, coded subroutines, numerical data, and output.
UNIVAC I 1951
The UNIVAC I delivered to the U.S. Census Bureau was the first commercial computer.
F.O.B. factory $750,000 plus $185,000 for a high speed printer
J. Presper Eckert and John Mauchly
IBM 650 1954
The IBM 650 magnetic drum calculator established itself as the first mass-produced computer, with the company selling 450 in one year. Spinning at 12,500 rpm, the 650´s magnetic data-storage drum allowed much faster access to stored material than drum memory machines.
TRADIC contained nearly 800 transistors instead of vacuum tubes. Transistors completely cold, highly efficient amplifying devices enabled the machine to operate on fewer than 100 watts, or one-twentieth the power required by comparable vacuum tube computers. The computer occupied only 3 cubic feet.
MIT TX0 1956
The TX-0 was the first general-purpose, programmable computer built with transistors. For easy replacement, designers placed each transistor circuit inside a "bottle," similar to a vacuum tube.
SAGE operator station 1958
SAGE — Semi-Automatic Ground Environment — linked hundreds of radar stations in the United States and Canada in the first large-scale computer communications network. An operator directed actions by touching a light gun to the screen.
DEC PDP-1 1960
The precursor to the minicomputer, DEC´s PDP-1 sold for $120,000 and included a cathode ray tube graphic display, needed no air conditioning and required only one operator. It´s large scope intrigued early hackers at MIT, who wrote the first computerized video game, SpaceWar!, for it.
IBM 1401 1961
The 1401 mainframe, the first in the series, replaced the vacuum tube with smaller, more reliable transistors and used a magnetic core memory. The machine´s success made a strong case for using general-purpose computers rather than specialized systems.
IBM System/360 1964
IBM announced the System/360, a family of six mutually compatible computers and 40 peripherals that could work together. The System/360 made the transition from discrete transistors to integrated circuits, and moved from punched-card equipment to electronic computer systems.
CDC 6600 1964
CDC´s 6600 supercomputer, performed up to 3 million instructions per second — a processing speed three times faster than that of its closest competitor, the IBM Stretch. The 6600 retained the distinction of being the fastest computer in the world until surpassed by its successor, the CDC 7600, in 1968. Part of the speed came from the computer´s design, which had 10 small computers, known as peripheral processors, funneling data to a large central processing unit.
DEC PDP-8 1965
Digital Equipment Corp. introduced the PDP-8, the first commercially successful minicomputer. The PDP-8 sold for $18,000, one-fifth the price of a small IBM 360 mainframe. The speed, small size, and reasonable cost enabled the PDP-8 to go into thousands of manufacturing plants, small businesses, and scientific laboratories.
The HP-2115 was a general purpose computer offering a computational power formerly found only in much larger computers. It supported a wide variety of languages, among them BASIC, ALGOL, and FORTRAN.
The Nova, had 32 kilobytes of memory, and sold for $8,000. The simple architecture of the Nova instruction set inspired Steve Wozniak´s Apple I board eight years later.
The Kenbak-1, the first personal computer, used standard medium-scale and small-scale integrated circuits, relied on switches for input and lights for output from its 256-byte memory.
Hewlett-Packard announced the HP-35 as "a fast, extremely accurate electronic slide rule" with a solid-state memory similar to that of a computer and had the ability to perform a broad variety of logarithmic and trigonometric functions, to store more intermediate solutions for later use, and to accept and display entries in a form similar to standard scientific notation.
TV Typewriter 1973
The TV Typewriter, provided the first display of alphanumeric information on an ordinary television set. It used $120 worth of electronics components. The original design included two memory boards and could generate and store 512 characters as 16 lines of 32 characters. A 90-minute cassette tape provided supplementary storage for about 100 pages of text.
The Micral was the earliest commercial, non-kit personal computer based on a micro-processor.
Xerox Alto 1974
The Alto was the first work station with a built-in mouse for input. The Alto stored several files simultaneously in windows, offered menus and icons, and could link to a local area network.
Scelbi 8H 1974
Scelbi was the first commercially advertised U.S. computer based on a microprocessor and was aimed at scientific, electronic, and biological applications. It had 4 kilobytes of internal memory and a cassette tape, with both teletype and oscilloscope interfaces.
Altair 8800 1975
The Altair 8800 computer kit was based on Intel´s 8080 microprocessor machine, coined the term “personal computer”, came with 256 bytes of memory (expandable to 64K) and an open 100-line bus structure. Bill Gates and Paul Allen licensed BASIC as the software language for the Altair.
The Video Display Module marked the first implementation of a memory-mapped alphanumeric video display for personal computers and allowed use of personal computers for interactive games.
The Tandem-16 was the first fault-tolerant computer, for online transaction processing. The banking industry rushed to adopt the machine, built to run during repair or expansion.
Apple I 1976
Steve Wozniak designed the Apple I, a single-board computer selling for $500. About 200 of the machines sold before the company announced the Apple II as a complete computer.
Cray I 1976
The Cray I was the first commercially successful vector processor. The fastest machine of its day, its speed came partly from its shape, a C, which reduced the length of wires and thus the time signals needed to travel across them.
The Commodore PET (Personal Electronic Transactor) was the first of several personal computers,came fully assembled and was straightforward to operate, with either 4 or 8 kilobytes of memory, two built-in cassette drives, and a membrane "chiclet" keyboard.
Apple II 1977
The Apple II was an instant success with its printed circuit motherboard, switching power supply, keyboard, case assembly, manual, game paddles, A/C powercord, and cassette tape with the computer game "Breakout." When hooked up to a color television set, the Apple II produced brilliant color graphics.
Tandy Radio Shack´s first desktop computer — sold 10,000 units. Priced at $599.95, the machine included a Z80 based microprocessor, a video display, 4 kilobytes of memory, BASIC, cassette storage, and easy-to-understand manuals that assumed no prior knowledge on the part of the consumer.
VAX 11/780 1978
The VAX 11/780 featured the ability to address up to 4.3 gigabytes of virtual memory, providing hundreds of times the capacity of most minicomputers.
IBM PC 1981
IBM introduced its PC, igniting a fast growth of the personal computer market. The first PC ran on a 4.77 MHz Intel 8088 microprocessor and used Microsoft´s MS-DOS operating system.
Adam Osborne completed the first portable computer, which weighed 24 pounds and cost $1,795. The machine featured a 5-inch display, 64 kilobytes of memory, a modem, software, and two 5 1/4-inch floppy disk drives.
Apollo DN100 1981
Apollo DN100 unveiled the first work station, offering more power than some minicomputers at a fraction of the price and were optimized to run the computer-intensive graphics programs common in engineering.
Cray XMP 1982
The Cray XMP, almost doubled the operating speed of competing machines with a parallel processing system that ran at 420 million floating-point operations per second, or megaflops. Arranging two Crays to work together on different parts of the same problem achieved the faster speed. Defense and scientific research institutes also heavily used Crays.
Apple Lisa 1983
Apple introduced its Lisa. The first personal computer with a graphical user interface, its development was central in the move to such systems for personal computers.
The Lisa ran on a Motorola 68000 microprocessor and came equipped with 1 megabyte of RAM, a 12-inch black-and-white monitor, dual 5 1/4-inch floppy disk drives and a 5 megabyte Profile hard drive.
Compaq PC Clone 1983
Compaq introduced first PC clone that used the same software as the IBM PC.
Apple launched the Macintosh, the first successful mouse-driven computer with a graphic user interface, with a single $1.5 million commercial during the 1984 Super Bowl. The commercial played on the theme of George Orwell´s "1984" and featured the destruction of Big Brother with the power of personal computing found in a Macintosh. It sold for $2,500 and included MacPaint, which made use of the mouse, and MacWrite, which demonstrated WYSIWYG (What You See Is What You Get) word processing.
IBM PC JR 1984
IBM released its PC Jr. and PC-AT. The PC Jr. failed, but the PC-AT, several times faster than original PC and based on the Intel 80286 chip, claimed success with its notable increases in performance and storage capacity, all for about $4,000. It also included more RAM and accommodated high-density 1.2-megabyte 5 1/4-inch floppy disks.
Connection Machine 1986
Used the concept of massive parallelism. The machine used 16,000 processors and could complete several billion operations per second. Each processor had its own small memory linked with others through a flexible network that users could alter by reprogramming rather than rewiring. The machine´s system of connections and switches let processors broadcast information and requests for help to other processors in a simulation of brainlike associative recall. Using this system, the machine could work faster than any other at the time on a problem that could be parceled out among the many processors.
IBM PC-RT 1986
The IBM PC/RT was the first R2000-based system and RISC-based workstation. It was a reduced instruction set computer - the simplest 20 percent of a computer´s instruction set does 80 percent of the work, including most base operations such as add, load from memory, and store in memory. It had 1 megabyte of RAM, a 1.2-megabyte floppy disk drive, and a 40-megabyte hard drive. It performed 2 million instructions per second.
IBM PS/2 1987
IBM introduced its PS/2 machines, with Intel’s 80386 chip and made the 3 1/2-inch floppy disk drive and video graphics array standard for IBM computers. IBM released a new operating system, OS/2, at the same time, allowing the use of a mouse with IBMs for the first time.
Apple cofounder Steve Jobs, who left Apple to form his own company, unveiled the NeXT. The computer failed but was recognized as an important innovation. The significance of the NeXT was the first personal computer to incorporate a drive for an optical storage disk, a built-in digital signal processor that allowed voice recognition, and object-oriented languages to simplify programming. The NeXT offered Motorola 68030 microprocessors, 8 megabytes of RAM, and a 256-megabyte read/write optical disk storage. At a base price of $6,500, the NeXT ran too slowly to be popular.