Download ThE fOuR gEnEraTioNs oF dIgiTaL CoMputEr

The four generations
of digital Computer
1.
2.
3.
4.
The first generation computers
The second generation computers
The third generation computers
The fourth generation computers
First Generation Computers
(1951-1958)
The first generation of computers used vacuum
tubes as their main logic elements
Punched cards to input and externally store
data;
Rotating magnetic drums for internal storage of
data in programs
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Program written
machine language (instructions written as a string of
0s and 1s)
Assembly language (a language that allowed the
programmer to write instructions in a kind of
shorthand that would then be "translated" by another
program called a compiler into machine language).
First Generations
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Computers had vacuum tubes, resistors, and welded
metal joints. They were large, slow, expensive and
produced a lot of heat.
It often broke down because of burned-out vacuum
tubes.
Computers also needed many experts to operate
them. In fact, when these computers running, people
stood by with shopping carts full of replacement.
In 1945, Presper Eckert and John Mauchly
developed the first operational electronic
digital computer, called ENIAC, for US Army.
ENIAC was over 1000 times faster than Mark
1, and could perform 5000 additions per
second.
ENIAC had more than 1800 vacuum tubes, and
took up to 1800 square feet of space. In addition,
the electrical current ENIAC required could power
more than a thousand modern computers. Today,
ENIAC’s technology could fit in a modern
wristwatch.
In 1951 the UNIVAC-1 became the first
commercially available electronic computer. This
computer was designed by Eckert and Mauchly (the
designers of the ENIAC) and built by the Remington
Rand corporation. The first of these computers was
delivered to US. Census Bureau.
Between 1951 and 1953 magnetic core memory
was developed. This memory consists of tiny ferrite
“donuts” that were arranged on a lattice of wires.
The polarity of their magnetization could be change
or detected by passing current through the wires.
This allowed each lattice point store one “bit” –
either 0 or 1. Magnetic core memory was the fastest
type of memory until the late 1980’s.
IBM 701, IMB’s first electronic business
computer.
Second Generation Computers
(1959-1963)
In the 1940s, discovered that a class of
crystalline
mineral
materials
called
semiconductors could be used in the design of a
device called a transistor to replace vacuum
tubes. Magnetic cores (very small donut-shaped
magnets that could be polarized in one of two
directions to represent data) strung on wire
within the computer became the primary internal
storage technology. Magnetic tape and disks
began to replace punched cards as external
storage devices.
Second Generation Computers
(1959-1963)
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Vacuum tubes replaced by transistors as a main logic
element.
Crystalline minerals materials called semiconductors could
be used in the design of a device called a transistor.
Magnetic tape and disks began to replace punched cards
as external storage devices.
Magnetic cores (very small donut-shaped magnets that
could be polarized in one of two directions to represent
data) strung on wire within the computer became the
primary internal storage technology.
High-level programming languages (program
instructions that could be written with simple words
and mathematical expressions), like FORTRAN
and COBOL, made computers more accessible to
scientists and businesses.
Instead of vacuum tubes, second generation
computers used transistors an exiting new
invention at the time. John Barden, Walter Brattain
and William Shockley of Bell Telephone
Laboratories invented the transistor. A transistor is
a small, solid-state component designed to monitor
the flow of the electric current.
Core memory stack
Tiny magnetic doughnuts.
Transistor
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Were smaller, faster, cheaper, required less power,
and produce less heat than vacuum tubes.
In computers, a transistor functions as an
electronic switch or bridge.
Transistors play an important role in electronic
circuits.
Transistors made second generations computers
faster and more reliable than first generations.
It can amplify signal, or open and close a circuit.
Circuits help make up electronic systems, and
electronic systems are what make electronic
computing possible.
Transistor
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Transistors
allowed
second
generations
computers to communicate over telephone lines.
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The transistor gave way to the concept of parallel
processor and multiprogramming.
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Unlike first generations computers, second
generations computers could run multiple
programs and could address input and output at
the same time.
Transistor
1961
Grace hopper, the woman that found the
first computer bug, finishes developing
COBOL
(Common
Business
Oriented
Language).
1964
Digital Equipment Corporation (DEC),
founded by Ken Olsen, release the first
minicomputer, the PDP-8.
1964
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IBM unveils the System/360, the first family of
computers.
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The IBM 360 is introduced in April and quickly
becomes the standard institutional mainframe
computer.
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By mid-80’s the 360 and its descendants will
have generated more than $100 billion in
revenue for IBM.
1965
Thomas Kurtz and John Kemeny of
Dartmouth
College
developed
BASIC
(Beginners All Purpose Symbolic Instruction
Code) as a computer language to help teach
people how to program.
NEXT REPORTER IS CLAUDETTE
BY: TONIE ;-)