Definition of a Computer
Simplest definition of a computer: A device that processes input and generates
output
Key words:
- Input
- Output
- Processes
- Information
Modern Computers are electronic, complex, and interactive, but can be reduced
to simple input-output processing devices
History of Computers: 3000 BC to Present History of Computers – Long, Long Ago
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History of Computers – Way Back When
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History of Computers – 19th Century
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Charles Babbage – 1792-1871
Analytical Engine 1833
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Ada Augusta – First Programmer
- Worked with Charles Babbage
- Programmed Analytical Engine
Discussion Question
- What was the biggest advance that led to modern computers?
- Electricity
- Transistor
- Microchip
- Data storage
Vacuum Tubes – 1930 – 1950s
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UNIVAC – 1951
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Grace Hopper |
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First Computer Bug – 1945
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First Transistor
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Integrated Circuits
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Birth of Personal Computers – Kenbak I – 1971
MITS Altair – 1975 (pictured)
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The First Microprocessor – 1971
- The Intel 4004 had 2,250 transistors
- four-bit chunks (four 1s or 0s)
- 108Khz
- 0.6 Mips (million instructions/sec)
- Pentium 133 – 300 Mips
- Called “Microchip”
Inside the Intel 4004 Microchip – 2250 Transistors
Generations of Electronic Computers
Generation | First
Generation I |
Second Gen.
II |
Third Gen.
III |
Fourth Gen.
IV |
Technology | Vacuum Tubes | Transistors | Integrated Circuits (multiple transistors) | Microchips (millions of transistors) |
Size | Filled Whole Buildings | Filled half a room | Smaller | Tiny – Palm Pilot is as powerful as old building sized computer |
Over the past 50 years, the Electronic Computer has evolved
rapidly.
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Using the following advancements, draw an “evolutionary chart” of how computers
evolved: - vacuum tube
- integrated circuit
- transistor
- microchip
IBM PC – 1981
- IBM-Intel-Microsoft joint venture
- First wide-selling personal computer used in business
- 8088 Microchip – 29,000 transistors
- 4.77 Mhz processing speed
- 256 K RAM (Random Access Memory) standard
- One or two floppy disk drives
Apple Computers
- Founded 1977
- Apple II released 1977 – widely used in schools
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Macintosh (left) – released in 1984, Motorola 68000 Microchip processor
(below) - Macintosh is first commercial computer with graphical user interface
(GUI) and pointing device (mouse)
1990s: Pentiums and Power Macs
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Early 1990s began penetration of computers into every niche: every desk,
most homes, etc. - Faster, less expensive computers paved way for this
- Windows 95 was first decent GUI for “PCs”
- Macs became more PC compatible – easy file transfers
- Prices have plummeted
How Electronic Computers Have Progressed
(1951-1970) (1968 vers.) |
(1971) |
(1981) |
(1984) |
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Circuits | Tubes,
Transistors, Integrated Circuits* |
130 Integrated Circuits | Intel 8088
Microchip – 29,000 Transistors |
Motorola 68000 | Intel P-III
Microchip – 7.5 million transistors |
Generation | I-II-III* | III | IV | IV | IV |
RAM Memory | 512 K | 265 Bytes | 256 K | 640 K | 128 Mb |
Speed | 1.3 MHz | 1 KHz | 4.77 Mhz | 8 MHz | 1000 MHz |
Storage | 100 MB Hard Drive | none | Floppy Drive | Floppy Drives | Hard Drive, Floppy, CD-Rom |
Size | Whole Room | Briefcase
(no monitor) |
Briefcase + Monitor | Two shoeboxes (integrated monitor) | Small Tower |
Cost | $1.6 million | $750 | $1595 | ~$4000 | $1500 |
*Early UNIVACs had vacuum tubes, middle models had transistors,
and by the end they used integrated circuits
Whats next for computers?
- Use your imagination to come up with what the next century holds for computers.
- What can we expect in two years?
- What can we expect in twenty years?