ThE fOuR gEnEraTioNs oF dIgiTaL CoMputEr

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Transcript ThE fOuR gEnEraTioNs oF dIgiTaL CoMputEr

The four generations of
digital Computer
1.
2.
3.
4.
The
The
The
The
first generation computers
second generation computers
third generation computers
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; and rotating magnetic drums for
internal storage of data in programs written
in machine language (instructions written as
a string of 0s and 1s) or 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).
In addition, first-generation computers
often broke down because of burned-out
vacuum tubes.
First generation computers also needed
many experts to operate them.
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.
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.
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

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. Circuits help make up
electronic systems, and electronic systems
are what make electronic computing
possible. Transistors allowed computers to
communicate over telephone lines. The
transistor gave way to the concept of
parallel processor and multiprogramming.
Transistor
1961
Grace hopper, the woman that found
the first computer bug, finishes
developing COBOL.
1964
Digital Equipment Corporation (DEC),
founded by Ken Olsen, release the first
minicomputer, the PDP-8.
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 ;-)