2. A computer is a general purpose device that can be
programmed to carry out a finite set of arithmetic or
logical operations. Since a sequence of operations can
be readily changed, the computer can solve more than
one kind of problem.
Conventionally, a computer consists of at least one
processing element, typically a central processing unit
(CPU) and some form of memory. The processing
element carries out arithmetic and logic operations,
and a sequencing and control unit that can change the
order of operations based on stored information.
Peripheral devices allow information to be retrieved
from an external source, and the result of operations
saved and retrieved.
3. Types of computer
Computers
Analog Digital Hybrid
Super Mini
computer computer Micro
Main frame
computer computer
4. Analog computer
Analog computer
An analog computer is a
form of computer that uses
the continuously
changeable aspects of
physical phenomena such
as electrical, mechanical, or
hydraulic quantities to
model the problem being
solved. In contrast, digital
computers represent
varying quantities
symbolically, as their
numerical values change.
5. Digital computer
DIGITAL COMPUTER
A computer that stores data in
terms of digits and proceeds in
discrete steps from one state to the
next.
The states of a digital computer
typically involve binary digits
which may take the form of the
presence or absence of magnetic
markers in a storage medium (see
memory), on-off switches or relays.
In digital computers, even letters,
words and whole texts are
represented digitally. Unlike analog
computers, digital computers can
only approximate a continuum by
assigning large numbers of digits to
a state description and by
proceeding in arbitrarily small
steps.
6. Hybrid computer
Hybrid computer
Hybrid computers are
computers that exhibit
features of analog
computers and digital
computers. The digital
component normally
serves as the controller
and provides logical
operations, while the
analog component
normally serves as a
solver of differential
equations.
7. Super computer
Super computer
supercomputer is a computer at
the frontline of current
processing capacity, particularly
speed of calculation.
Supercomputers were
introduced in the 1960s and
were designed primarily by
Seymour Cray at Control Data
Corporation (CDC), and later at
Cray Research. While the
supercomputers of the 1970s
used only a few processors, in
the 1990s, machines with
thousands of processors began
to appear and by the end of the
20th century, massively parallel
supercomputers with tens of
thousands of "off-the-shelf"
processors were the norm
8. Main frame computer
Main frame computer
Mainframe computers (colloquially
referred to as "big iron" are
computers used primarily by
corporate and governmental
organizations for critical
applications, bulk data processing
such as census, industry and
consumer statistics, enterprise
resource planning, and transaction
processing. The term originally
referred to the large cabinets that
housed the central processing unit
and main memory of early
computers.
Later, the term was used to
distinguish high-end commercial
machines from less powerful
units.[citation needed] Most large-
scale computer system architectures
were established in the 1960s, but
9. Mini computer
Mini computer
A minicomputer, or colloquially mini, is a
class of smaller computers that evolved in
the mid-1960s and sold for much less
than mainframe and mid-size computers
from IBM and its direct competitors. In a
1970 survey, the New York Times
suggested a consensus definition of a
minicomputer as a machine costing less
than 25 000 USD, with an input-output
device such as a teleprompter and at least
4K words of memory, that is capable of
running programs in a higher level
language, such as Fortran or Basic.[1] The
class formed a distinct group with its own
hardware architectures and operating
systems.
10. Micro computer
Micro computer
A microcomputer is a small, relatively
inexpensive computer with a
microprocessor as its central
processing unit (CPU).
It includes a microprocessor, memory,
and input/output (I/O) facilities.
Microcomputers became popular in
the 1970s and 80s with the advent of
increasingly powerful microprocessors.
The predecessors to these computers,
mainframes and minicomputers, were
comparatively much larger and more
expensive (though indeed present-day
mainframes such as the IBM System z
machines use one or more custom
microprocessors as their CPUs). Many
microcomputers (when equipped with
a keyboard and screen for input and
output) are also personal computers
(in the generic sense).
