2. The vacuum tube was invented in
1906 by an electrical engineer named
Lee De Forest (1873–1961). During the
first half of the twentieth century, it
was the fundamental technology that
was used to construct radios,
televisions, radar, X-ray machines,
and a wide variety of other electronic
devices. It is also the primary
technology associated with the first
generation of computing machines.
Vacuum tubes are glass tubes with circuits inside.
3. 3
The main features of the first generation are −
Vacuum tube
technology
Unreliable
Very costly
Generated a lot of heat
Slow input and output
devices
Huge size
Need of AC
Non-portable
Consumed a lot of electricity
4. Generations of first computer:
4
• The first computer to be built in 1946 with vacuum tubes was the Electronic
Numerical Integrator and Computer or simply ENIAC. This computer was huge
and occupied around 15,000 square feet of floor space and weighed in at an
astonishing 30 tonnes!
• The second computer in this line was the EDSAC or Electronic Delay Storage
Automatic Calculator which had the added capacity to store programs than its
predecessor.
• The third machine to come along was the UNIVAC or Universal Automatic
Computer which was created by scientists John Mauchly and John Presper
Eckert and is mostly regarded as the first modern computer.
• In 1953 IBM announced their first commercially mass-produced produced
computer in the IBM 650. Support for the IBM 650 and its components units
was discontinued in 1969.·
• The IBM 701 was the last in the line of the first generation computers and was
IBMs first scientific computer. The 701 was succeeded by the more advanced
IBM 704 in 1956.
Some of the computers that made up this generation include:
5. During the period of 1940 to 1956 first generation of
computers were developed. The first generation
computers used vacuum tubes for circuitry and magnetic
drums for memory, and were often enormous, taking up
entire rooms. The vacuum tube was developed by Lee
DeForest. A vacuum tube is a device generally used to
amplify a signal by controlling the movement of electrons
in an evacuated space. First generation computers were
very expensive to operate and in addition to using a great
deal of electricity, generated a lot of heat, which was often
the cause of malfunctions.
FIRST GENERATION OF COMPUTERS
5
7. UNIVAC (Universal Automatic Computer) was the
first commercially general purpose electronic
computer. John Eckert and John Mauchly at the
Moore School of Engineering, Pennsylvania
developed it in 1951. It was used for the analysis
of 1952 Presidential Election in the United States.
It was 8 feet high, 15 feet long and weighed 5
tons. It contained 5600 tubes, 18000 crystal
diodes, and 300 relays. A magnetic tape was used
for data input and output.
Universal Automatic Computer (UNIVAC)
7
8. John Mauchly and J.P. Eckert also proposed the
development of EDVAC. The conceptual design for EDVAC
electronic computer to use the stored program concept
introduced by John Von Neumann. Unlike the ENIAC, it
used binary number rather than decimal. The University
of Pennsylvania built the EDVAC for the U.S. Army’s
Ballistics Research Laboratory at the Aberdeen Proving
Ground. EDVAC had almost 6000 vacuum tubes and
12000 diodes. It consumed 56kW of power. It covered
490 feet square of floor and weighed 7850kg.
8
Electronic DiscreteVariable Automatic
Computer (EDVAC)
9. EDSAC (Electronic Delay Storage Automatic
Calculator) was developed by a group of scientists,
headed by Professor Maurice Wilkes at Cambridge
University, England, in 1949. It was also based on
the stored program concept and one of the first to
use binary digits. The input and output were
provided by a paper tape. It could do about 700
additions per second and 200 multiplications per
second. The machine occupied a room, which
measured 5/4 meters.
Electronic Delay Storage Automatic Calculator (EDSAC)
9
10. Electronic Numerical Integrator and Calculator (ENIAC)
was designed by John Mauchly and John Presper Eckert
in 1946 at the Moore School of Electrical Engineering,
University of Pennsylvania. It was the first electronic
computer. ENIAC was initially built for the United States
military to calculate the paths of artillery shells. It
contained 18000 vacuum tubes, 7200 crystal diodes,
1500 relays, 70000 resistors, 10000 capacitors and
around 5 million hand-soldered joints. It weighed
nearly 30 tons and consumed 160 kW of power. Input
was possible from an IBM card reader while an IBM
punch card was used for output.
Electronic Numerical Integrator and Calculator (ENIAC)
10
13. 13
These computers fast and could
calculate data in millisecond.
Vacuum tubes were the only
electronic component available during
those days.
Vacuum tube technology made
possible to make electronic digital
computers.
Easily available and inexpensive.
Tactile sensitivity is preserved.
Color-coded for easier and faster
identification of readings.
14.
15. 15
The computers were very large in size.
They consumed a large amount of energy.
They heated very soon due to thousands of vacuum
tubes.
They were not very reliable.
Air conditioning was required.
Constant maintenance was required.
Non-portable.
Costly commercial production.
Costly commercial production.
Limited commercial use.
Very slow speed.
Limited programming capabilities.
Used machine language only.
Used magnetic drums which provide very less data
storage.