Lesson 3: Computer Generation

Definition of a Computer
- Information Processor
- Input and Output
- Inputs, outputs, processes and stores information
- Physical:  Keyboard, monitor, etc. – are these necessary components?

Abacus (3000 B.C.)
- beads on rods to count and calculate
- still widely used in Asia!

Slide Rule
- Slide Rule 1630
- based on Napier’s rules for logarithms
- used until 1970s

Jacquard Loom (1801)
- first stored program - metal cards
- first computer manufacturing
- still in use today!

Charles Babbage - 1792-1871
- Difference Engine c.1822
*** huge calculator, never finished
- Analytical Engine 1833
*** could store numbers
*** calculating “mill” used punched metal cards for instructions
*** powered by steam!
*** accurate to six decimal places

Vacuum Tubes - 1941 - 1956
- First Generation Electronic Computers used Vacuum Tubes
- Vacuum tubes are glass tubes with circuits inside. 
- Vacuum tubes have no air inside of them, which protects the circuitry.

UNIVAC - 1951
- first fully electronic digital computer built in the U.S.
- Created at the University of Pennsylvania
- ENIAC weighed 30 tons
- contained 18,000 vacuum tubes
- Cost a paltry $487,000

Grace Hopper
- Programmed UNIVAC
- Recipient of Computer Science’s first “Man of the Year Award”

First Computer Bug - 1945
- Relay switches part of computers
- Grace Hopper found a moth stuck in a relay responsible for a malfunction
- Called it “debugging” a computer

First Transistor
Uses Silicon
developed in 1948
won a Nobel prize
on-off switch

Second Generation Computers used Transistors, starting in 1956
– Computers began to incorporate Transistors
- Replaced vacuum tubes with Transistors

Third Generation – 1964-1971
- 1964-1971
- Integrated Circuit
- Operating System
- Getting smaller, cheaper

The First Microprocessor – 1971
Intel 4004 Microprocessor
- had 2,250 transistors
- four-bit chunks (four 1’s or 0’s)
- 108Khz
- Called “Microchip”

What is a Microchip?
- Very Large Scale Integrated Circuit (VLSIC)
- Transistors, resistors, and capacitors
- 4004 had 2,250 transistors
- Pentium IV has 42 MILLION transistors
- Each transistor 0.13 microns (10-6 meters)

4th Generation – 1971-present
MICROCHIPS!
Getting smaller and smaller, but we are still using microchip technology

5th Generation (present)
- Artificial Intelligence