What is a computer & type of computers?

Computer-
Definition - What does a computer mean?
A computer is a machine or device that performs processes, calculations and operations supported directions provided by a computer code or hardware program. It’s designed to execute applications and provides a range of solutions by combining integrated hardware and software system elements.
Types-

There are Four Different Computer Types-

We have four different computer types classified according to their performance, power, and size. A computer is an electronic device that accepts data, processes it, stores, and then produces an output.
There are different computer types available depending on the number of users they can support at any one time, their size, and power. In this hub, we are going to have a look at the difference between supercomputers, mainframe, mini, and microcomputers.
1. Supercomputers – Supercomputers are very expensive, very fast, and the most powerful computers we have in the world.
Supercomputers are optimized to execute a few numbers of programs. This makes it possible for them to execute these few programs at a very high speed.
Due to their inhibiting cost, they are used in high-end
places like in scientific research centers. The
supercomputer consists of thousands of processors
making it clock very high speeds measured by
petaflops.
These computer types are also very large in size due
to the numerous parts and components involved in
their design.
A good example of a Supercomputer is Tianhe-2: TH-
IVB-FEP Cluster; National Super Computer Center in
Guangzhou, China; 3.12 million cores (33.86 petaflops/
s).
2. Mainframe computers — These are large and
expensive computer types capable of supporting
hundreds, or even thousands, of users simultaneously.
Thus, they are mostly used by governments and large
organizations for bulk data processing, critical
applications, transaction processing, census, industry
and consumer statistics among others. They are
ranked below supercomputers.
3. Minicomputers — Minicomputers are mid-sized
computers. In terms of size and power,
minicomputers are ranked below mainframes. A
minicomputer is a multiprocessing system capable of
supporting from 4 to about 200 users simultaneously.
The use of the term Minicomputer has diminished and
they have merged with servers.
4. Microcomputers or Personal computers – A
personal computer is a computer designed to be used
by one user at a time. The term microcomputer
relates to the microprocessor which is used with a
personal computer for the purpose of processing data
and instruction codes. These are the most common
computer types since they are not very expensive.

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