01 History of Computers.pptx
-
Upload
mcharity-tonii -
Category
Documents
-
view
218 -
download
0
Transcript of 01 History of Computers.pptx
HISTORY of COMPUTERS
History of Computers
Who invented the computer? is not a question with a simple answer. The real answer is that many inventors contributed to the history of computers and that a computer is a complex piece of machinery made up of many parts, each of which can be considered a separate invention.
-Mary Bellis
2
What was it before computers?
Manual calculators
abacus
Napier bones
slide rule
3
What was it before computers?
Mechanical calculators
Schickards calculator (1623)
series of interlocking geard
Pascaline (1642)
performed basic arithmetic operations
4
What was it before computers?
Mechanical calculators
Leibniz calculator (1673)
similar with pascaline
de Colmars Arithmometer (1820)
first mass produced mechanical calculator
5
What was it before computers?
Difference engine (1822)
device proposed by Charles Babbage that would operate using steam engine
too complicated to work until 1853
6
What was it before computers?
Analytical engine (1834)
new device designed by Babbage
never completed
design embodies many concepts that define modern computers
memory
programmable processor
output device
user-definable input
data
7
Computer Prototypes
Prototype
experimental device that must be further developed and perfected before going into production and becoming widely available.
8
ABC (circa 1942)
Atanasoff-Berry Computer
John Atanasoff and Clifford Berry (Iowa State University)
Represented several innovations in computing
binary system of arithmetic
parallel processing
regenerative memory
separation of memory and computing functions.
9
Atanasoff-Berry Computer
10
Z1 (1936)
Mechanical calculator, first binary computer
Invented by Konrad Zuse
Z2 invented in 1939
first fully functioning electro-mechanical computer
Z3 invented in 1941
digital computer based on a binary floating-point number and switching system
used old movie film instead of paper and punch card to store data
11
Z1
Z2
Z3
12
MARK Series (1944)
Designed by Howard Aiken and Grace Hopper at Harvard University
MARK I in 1944
Giant roomful of noisy, clicking metal parts, 55ft X 8ft
Used by US Navy for gunnery and ballistic calculations
In operation until 1959
13
Harvard MARK Computer
14
ENIAC (1945)
Electronic Numerical Integrator and Computer
Developed by John Mauchly and J. Presper Eckert
Sponsored by the US military
for writing artillery-firing tables
15
ENIAC
16
First Generation Computers
Characterized by their use of vacuum tubes to store individual bits of data
Vacuum tube
An electronic device that controls the flow of electrons in a vacuum
Respond more quickly than mechanical relays, resulting in faster computations, but they also have several disadvantages
17
UNIVAC (1951)
Universal Automatic Computer
Developed by John Mauchly and J. Presper Eckert
Considered by most historians to be the first commercially successful digital computer
Could read data at the rate of 7,200 characters per second, and complete 2.25 million instruction cycles per second
18
UNIVAC 1
19
Second Generation Computers
Generations of computers that used transistors instead of vacuum tubes
Transistors
regulate current or voltage flow and act as a switch for electronic signals
performed functions similar to vacuum tubes, but they were much smaller, cheaper, less power hungry, and more reliable
20
Third Generation Computers
Based on integrated circuits
Became possible in 1958, when Jack Kilby at Texas Instruments and Robert Noyce at Fairchild Semiconductor independently developed integrated circuits
Integrated circuit
Packed the equivalent of thousands of vacuum tubes or transistors onto a single miniature chip, vastly reducing the physical size, weight, and power requirements for devices such as computers
21
First Integrated Circuit
22
Third Generation Computers
First computers to incorporate ICs
RCA Spectra 70
IBM 360
23
Third Generation Computers
DEC PDP-8
The first commercially successful minicomputer
IBM AS/400
One of the few remaining devices that could be classified as a minicomputer
24
Fourth Generation Computers
Microprocessor-based computer systems that were faster, smaller, and even less expensive than third-generation computers
Microprocessor
developed by Ted Hoff in 1971
Intel 4004
equivalent to 2,300 transistors
4 bit data path
ran at 108 KHz
25
Home Computers (early 1970s)
Based on microprocessors
Utilize LSI (large scale integration) and VLSI (very large scale integration)
Smaller, faster and more complex than computers built on ICs
26
Scelbi
Scientific Electronic Biological Computer
27
MARK 8
28
Altair 8800
29
IBM 5100
30
Personal Computer (1981)
IBM PC
Introduced by IBM
MS-DOS 1.0 operating system
Intel 8088 processor
Success lead many other companies to develop their products IBM compatible
IBM PC XT
The IBM PC was soon followed by the IBM PC XT, which featured RAM upgradable to 640 KB, and a 10 MB hard disk drive.
31
First IBM PCs
32
Personal Computers by Apple
Apple I
a kit containing a system board with 4 KB of RAM that sold for $666.66.
released during 1976 by Apple Computer Corporation founded by Steve Jobs and Steve Wozniak.
Apple II
preassembled computer which featured color graphics, expansion slots, a disk drive, a 1.07 MHz 6502 processor, and 16 KB of RAM for $1,195.
33
Personal Computers by Apple
34
Apple Lisa
Computer developed by Apple Computer, Inc.
Developed starting 1978, released 1983
Features:
protected memory, cooperative multitasking
hard disk based OS, built-in screensaver
advanced calculator, numeric keypad
support for up to 2MB RAM
Motorola 68000 CPU running at 5 MHz
35
Apple Lisa
36
Apple Macintosh
Featured a graphical user interface that made programs easier to use than those on the command-line-based IBM PC.
37
Microsoft Windows 1.0 (1983)
Announced this new OS in 1983 but was released in 1985
Originally called Interface Manager but Windows prevailed because it best describes the boxes or computing windows that are fundamental to the new system
Provides graphical user interface (GUI)
Multitasking environment for IBM computers
38
Windows 1.0 Screenshot
39
Trends
Desktop computers were very famous and still are available
Trend goes to portable devices
Portable computers became smaller, lighter and popular
outsold desktop computers in 2005
Apple iPhone ushered in the era of handheld computing devices
Smartphones outsold desktop and notebook computers in 2011
40