Computers, Then and Now

Sorce 1: http://sixrevisions.com/resources/the-history-of-computers-in-a-nutshell/

* Mid 1800’s - 1930’s: Early Mechanical computers * invented by Charles Babbage in mid 1800’s - called “babbage engines” * These early computers were never completed during Babbage’s lifetime, but their complete designs were preserved. Eventually, one was finished being built in 20021930s: Electro-Mechanical Computers * 1930’s: Electro-mechanical Computers * Electro-mechanical computers generally worked with relays and/or vacuum tubes, which could be used as switches. * The differential Analyzer built in 1930—used purely mechanical internals but employed electric motors to power them. * 1940’s: Electronic Computers * The first electronic computers were developed during the World War II, with the earliest of those being the Colossus. * The Colossus was developed to decrypt secret German codes during the war. * used vacuum tubes and paper tape and could perform a number of Boolean (e.g. true/false, yes/no) logical operations. * 1950’s: The First Commercial Computers * The J. Lyons Company, which was a British catering firm, invested heavily in some of these early computers. In 1951, LEO (Lyons Electronic Office) became the first computer to run a regular routine office job. By November of that year, they were using the LEO to run a weekly bakery valuations job. * The UNIVAC was the first commercial computer developed in the US. * It was the first mass-produced computer, with more than 45 units eventually produced and sold. * IBM 701 was another notable development in early commercial computing; it was the first mainframe computer produced by IBM. * Around same time: FORTRAN programming language was being developed * A smaller IBM 650 was developed in the mid-1950s, and was popular due to its smaller size and footprint (it still weighed over 900kg, with a separate 1350kg power supply). * Mid- 1950’s: Transistor computers * The first disk drive, the IBM 350 RAMAC, was the first of these introduced in 1956. * Remote terminals also became more common with these second-generation computers. * 1960’s: Microchip and Microprocessor * The microchip (or integrated circuit) is one of the most important advances in computing technology. * Many overlaps in history existed between microchip-based computers and transistor-based computers throughout the 1960s, and even into the early 1970s. * three microprocessor designs that came out at about the same time. The first was produced by Intel (the 4004). Soon after, models from Texas Instruments (the TMS 1000) and Garret AiResearch (the Central Air Data Computer, or CADC) followed. * 1970’s: personal computers * The first personal computers were built in the early 1970s. Most of these were limited-production runs, and worked based on small-scale integrated circuits and multi-chip CPUs. * The Altair 8800 was the first popular computer using a single-chip microprocessor. It was also sold in kit form to electronics hobbyists, meaning purchasers had to assemble their own computers. * 1977 saw the rise of the "Trinity" (based on a reference in Byte magazine): the Commodore PET, the Apple II, and the Tandy Corporation’s TRS-80. These three computer models eventually went on to sell millions. * These early PCs had between 4kB and 48kB of RAM. The Apple II was the only one with a full-color, graphics-capable display, and eventually became the best-seller among the trinity, with more than 4 million units sold. * 1980’s - 1990’s: The early notebooks and laptops *
Sorce 2: http://homepage.cs.uri.edu/faculty/wolfe/book/Readings/Reading03.htm * The progression in hardware representation of a bit of data: 1. Vacuum Tubes (1950s) - one bit on the size of a thumb; 2. Transistors (1950s and 1960s) - one bit on the size of a fingernail; 3. Integrated Circuits (1960s and 70s) - thousands of bits on the size of a hand 4. Silicon computer chips (1970s and on) - millions of bits on the size of a finger nail.

* The progression of the ease of use of computers: 5. Almost impossible to use except by very patient geniuses (1950s); 6. Programmable by highly trained people only (1960s and 1970s); 7. Useable by just about anyone (1980s and on). * first substantial computer was the giant ENIAC machine by John W. Mauchly and J. Presper Eckert at the University of Pennsylvania * ENIAC (Electrical Numerical Integrator and Calculator) * used a word of 10 decimal digits instead of binary ones like previous automated calculators/computers * first machine to use more than 2,000 vacuum tubes, using nearly 18,000 vacuum tubes * took up over 167 square meters (1800 square feet) of floor space * punched-card input and output and arithmetically had 1 multiplier, 1 divider-square rooter, and 20 adders employing decimal "ring counters," which served as adders and also as quick-access (0.0002 seconds) read-write register storage. * ENIAC could be considered programmable * ENIAC is generally acknowledged to be the first successful high-speed electronic digital computer (EDC) * productively used from 1946 to 1955 * A controversy developed in 1971, however, over the patentability of ENIAC's basic digital concepts, the claim being made that another U.S. physicist, John V. Atanasoff, had already used the same ideas in a simpler vacuum-tube device he built in the 1930s while at Iowa State College * In 1973, the court found in favor of the company using Atanasoff claim and Atanasoff received the acclaim he rightly deserved. * Progression of Hardware * 1950's two devices would be invented that would improve the computer field and set in motion the beginning of the computer revolution