A computer is an electronic device which takes
the input through input devices, processes it and gives output through
output devices.
Computer works with 0’s and 1’s (binary).
Like all electronic devices works with dc power
supply.
The term computer is derived
from the Latin term ‘computare’,
this means to calculate or
programmable machine.
Computer cannot do
anything without a Program.
It represents the decimal numbers through a string of binary digits.
The Word 'Computer' usually refers to the central processor Unit
plus Internal memory.
Charles Babbage is called the "Grand Father" of
the computer.
The First mechanical computer designed by Charles
Babbage was called Analytical
Engine.
It uses read-only memory in the form of punch
cards..
Four Functions about computer are:
Input (Data):
Input is the raw information entered into a computer
from the input devices. It is the collection of letters, numbers, images etc.
Process:
Process is the operation of data as per given
instruction. It is totally internal process of the computer system.
Output:
Output is the processed data given by computer
after data processing. Output is also called as Result. We can save these
results in the storage devices for
the future use.
Computer Classification: By Size and Power
Computers differ based on their data processing
abilities. They are classified according to purpose, data handling and
functionality.
According to functionality, computer's are classified as:
• Analog
Computer: A computer that
represents numbers by some continuously variable physical quantity, whose
variations mimic the properties of some system being modeled.
• Personal
computer: A personal computer is a computer small and
low cost. The term "personal computer" is used to
describe desktop computers (desktops).
• Workstation: A terminal or desktop computer in a network. In
this context, workstation is just a generic term for a user's machine (client
machine) in contrast to a "server" or "mainframe."
• Minicomputer: A minicomputer isn't
very mini. At least, not in the way most of us think of mini. You know how big
your personal computer is
and its related family.
• Mainframe: It refers to the kind of large computer that
runs an entire corporation.
• Supercomputer: It is the biggest, fastest, and most expensive
computers on earth.
k computer
• Microcomputer: A microcomputer is a small,relatively expansive computer with a microprocessor as its CPU.it includes a micro processor,memory,and input/output facilities .
