1 History of Computers Source – IEEE 50 th anniversary of modern computing timeline Up to 50 years ago

2 History of Computing 1612 –John Napier made the first printed use of the decimal point 1622 –William Oughtred created the slide rule (originally circular) based on Napier's logarithms that was to be the primary calculator of engineers through the 19th and early 20th centuries.

Blaise Pascal created an adding machine with automatic carries from one position to the next.

Charles Babbage –design the Difference Engine for computing the entries in navigation and other tables. Users did not have to understand underlying algorithm

Babbage realizes difference engine is special purpose Begins work on Analytic Engine –Has basic components of a modern computer BUT –Did not document well –Ideas unaccepted due to lack of communication

Conrad Zuse –developed his Z- 1 computer in his parent's living room, a relay computer, using binary arithmetic. Didn’t get funding.

John Mauchly and J. Presper Eckert Worked on ENIAC at Penn –Electronic Numerical Integrator and Calculator First general purpose computer

Harvard Mark I First large scale, automatic, general purpose, electromechanical calculator Same purpose as Babbage’s machine

ENIAC

10 ENIAC Eckert on left and Goldstine (army liason) on right, holding an arithmetic unit from the ENIAC

11 ENIAC Eckert and Mauchly represented a stepping stone towards the true computer not the ultimate in the state-of-the-art technology BUT … construction was completed programmed by rewiring interconnections

EDSAC –Electronic Delay Storage Automatic Computer Stored program computer Four others being built at the same time

13 von Neumann Von Neumann, Burks, and Goldstine wrote memos/drafts on the first logical design of computers Didn’t credit Mauchly and Eckert Basic architecture is still widely used 50 years later

14 The Mark I computer