4-1 Early Developments in Electronic Data Processing 4- 2 Mark 1 4 - 3 The Eniac 4 - 4 The Edvac 4 – 5 Computer Generations 4 – 6 First Generation Computers 4 – 7 Second Generation Computers 4 – 8 Third Generation Computers 4 – 9 Fourth Generation Computer
Mark I Howard Aiken began work on the Mark I at Harvard University Mark I digital computer was completed in 1944 Mark I official name was Automatic Sequence Controlled Calculator. Mark I functions: Could perform arithmetic operations Could locate information stored in tabular form.
Mark I Processed numbers up to 23 digits longs and could multiply three eight-digit numbers in 1 second. It was not an electronic computer but as rather an electromechanical one
THE ENIAC ENIAC – Electronic Numerical Integrator and Calculator ENIAC was developed by Presper Eckert Jr. aand John Mauchly from 1943 to 1946. It has 18,000 vacuum tubes and required the manual setting of switches. It could perform 300 multiplications per second
The EDVAC EDVAC is the modified version of ENIAC EDVAC – Electronic Discrete variable automatic Computer EDVAC employs binary arithmetic John von Neumann invented the EDVAC
Computer Generations First Generation Computers Second Generation Computers Third Generation Computers Fourth Generation Computers
First Generation Computers ( 1951-1959) The use vacuum tubes in place of relays as a means of storing data in memory and the use of stored-program concept. It requires 3.5 KW of electricity per day to keep the vacuum tubes running
Second Generation Computers ( 1959-1964) Solid-state components ( transistors and diodes) and magnetic core storage formed the basis for the second generation of computers
Third Generation Computers ( 1965-1970) Integrated solid-state circuitry, improved secondary storage devices and new input/output devices were the most important advances in this generation.
Fourth Generation Computers ( 1970 to present) The major innovations were in the development of microelectronics and in the development of different areas in computer technology such as: multiprocessing, multiprogramming, miniaturization, time sharing , operating speed and virtual storage.