Generation Of Computers Flashcards
First Generation Years
1940 - 1956
VACUUM TUBE also known as
Thermionic Value Based Machines
VACUUM TUBE
First generation computer were Vacuum Tubes/thermionic value based machines
for circuitry and magnetic drums for memory.
Magnetic drum
metal cylinder coated with magnetic iron-oxide material on which data and program can be stored.
Input
based on punched cards and paper tape
Output
Was in the form of printouts
Examples of First Generation Computers
ENIAC, EDVAC, and UNIVAC
Characteristics of First Generation Computers (4)
• These computers were based on vacuum tube technology.
• These were the fastest computing devices of their time.
• These computers were very large, and required a lot of space for installation.
• These were non-portable and very slow equipments
Second Generation Computer Years
1956 - 1963
TRANSISTORS
Used by Second Generation Computers
made up of semiconductor material like germanium and silicon
usually had three leads and performed electrical functions such as voltage, current or power amplification with low power requirement.
Effects of Transistors on Computers
Since transistor is a small device, the physical size of computers was greatly reduced. Computers became smaller, faster, cheaper, energy-efficient and more reliable than their predecessors.
Magnetic Cores
were used as primary memory and magnetic disks as secondary storage devices.
still relied on punched cards for input and printouts for output
In second generation computers
Second Generation Computers example
PDP – 8 , IBM 1401 and IBM 7090
Third Generation Computer Years
1964 - Early 1970
Integrated Circuits (ic)
Trait of third gen computer
consists of a single chip with many components such as transistors and resistors fabricated on it.
replaced several individually wired transistor.
Effects of Integrated Circuits on Computers
replaced several individually wired transistor. This development made computers smaller in size, reliable and efficient.
How did users interact with third generation computers?
Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with operating system.
Third Generation Computers Example
NCR 395 and B6500
Characteristics of Second Gen Computers (3)
• These machines were based on transistor technology • These were smaller as compared to the first generation computers.
• These were more portable and generated less amount of heat.
Characteristics of Third Gen Computers (3)
• These computers were based on integrated circuit (ic) technology.
• They were able to reduce computational time from micro seconds to nano seconds.
• Extensive use of high – level language became possible.
Fourth Generation Computer Years
Early 1970 - Till Date
Microprocessors
still based on the intergrated circuit, these have been made readily available to use because of the development of the microprocessor.
Utilized by 4th Gen computers
What did the 4th Gen Computers lead to?
an era of large scale integration (LSI) and very large scale integration (vlsi) technology.
LSI meaning
Large Scale Integration
