Computer Applications, Types OF Computer Kardan University Kabul Afghanistan

1. Types Of Computer
Prepared By: Engr. Ahmad Sameer Nawab
Kardan University

2. Classification Of Computers
 Computers are classified and categorized into three sort of categories
according to their specific number of functionalities.
 By Type
 By Size
 By Function

3. Types Of Computer
 Computer by size has been divided into three sub-categories which they have
various number of functionalities corresponded to them.
 Hybrid Computers
 Analogue Computers
 Digital Computers

4. Analogue Computer Type
 Analogue types of Computer uses what is known as analogue signals that are
represented by a continuous set of varying voltages and are used in scientific
research centers For example hospitals and flight centers
 With analogue types of computer no values are represented by physical
measurable quantities For example voltages.
 Analogue computer types program arithmetic and logical operations by measuring
physical changes for example temperatures or pressure.
A 1960 New mark analogue computer, made up
of five units. This computer was used to solve
differential equations and is currently housed at
the Cambridge Museum of Technology.
The name "Dornier" is normally linked with
advanced aircraft design.
www.analoguemuseum.org

5. Digital Computer type
 With these types of computers operation are on electrical input that can attain
two inputs, states of ON=1 and state of OFF = 0. With digital type of computers
data is represented by digital of 0 and 1 or off state and on state. Digital
computer type recognizes data by counting discrete signal of (0 0r 1), they are
high speed programmable.
 they compute values and stores results.

6. Hybrid type of Computer
 Hybrid computer types are very unique, in the sense that they combined both
analogue and digital features and operations.
 With Hybrid computers operate by using digital to analogue convertor and
analogue to digital convertor.
 By linking the two types of computer above you come up with this new
computer type called Hybrid.

7. Hybrid Computer, System
 hybrid computers should be distinguished from hybrid systems. The latter may
be no more than a digital computer equipped with an analog-to-digital converter
at the input and/or a digital-to-analog converter at the output, to convert analog
signals for ordinary digital signal processing, and conversely, e.g., for driving
physical control systems, such as servomechanisms.
 A servomechanism, sometimes shortened to servo, is an automatic device that
uses error-sensing negative feedback to correct the performance of a
mechanism.
 The term correctly applies only to systems where the feedback or error-
correction signals help control mechanical position, speed or other parameters.
For example, an automotive power window control is not a servomechanism, as
there is no automatic feedback that controls position—the operator does this by
observation. By contrast the car's cruise control uses closed loop feedback, which
classifies it as a servomechanism.

8. Computers By Size
 Computer has been categorized into Four other types according to it’s size.
 Microcomputers (Personal computers)
 Minicomputers (Midrange computers)
 Mainframe computers
 Supercomputer
 These four types are sub-parts of Digital Computers

9. Microcomputers
 Microcomputers are the most common type of computers used by people today, whether in a
workplace, at school or on the desk at home. The term ―microcomputer‖ was introduced with
the advent of single chip microprocessors.
 The term "microcomputer" itself is now practically an anachronism.
 Desktop Computers
 In-car computers (―carputers‖) – Built into a car, for entertainment, navigation, etc.
 Game consoles – Fixed computers specialized for entertainment purposes (video games).
 A separate class is that of mobile devices:
 Laptops, notebook computers and Palmtop computers – Portable and all in one case.
 Varying sizes, but other than smart books expected to be ―full‖ computers without limitations.
 Tablet computer – Like laptops, but with a touch-screen, sometimes entirely replacing the
physical keyboard.
 Smartphones, smart books and PDAs (personal digital assistants) – Small handheld computers
with limited hardware.
 Programmable calculator– Like small handhelds, but specialized on mathematical work.
 Handheld game consoles – The same as game consoles, but small and portable.

10. Micro-Computers
Computermusem.li

11. Minicomputers
 A minicomputer (colloquially, mini) is a class of multi-user computers that
lies in the middle range of the computing spectrum, in between the smallest
multi-user systems (mainframe computers) and the largest single-user systems
(microcomputers or personal computers).
 The contemporary term for this class of system is midrange computer, such as
the higher-end SPARC, POWER and Itanium -based systems from Oracle
Corporation, IBM and Hewlett-Packard.
 E.g.- Laboratory computers

12. Mainframe computers
 The term mainframe computer was created to distinguish the
traditional, large, institutional computer intended to service multiple
users from the smaller, single user machines. These computers are
capable of handling and processing very large amounts of data
quickly. Mainframe computers are used in large institutions such as
government, banks and large corporations. They are measured in
MIPS (million instructions per second) and respond to up to 100s of
millions of users at a time.

13. Supercomputer
 A supercomputer is focused on performing tasks involving intense
numerical calculations such as weather forecasting, fluid dynamics,
nuclear simulations, theoretical astrophysics, and complex scientific
computations. A supercomputer is a computer that is at the frontline
of current processing capacity, particularly speed of calculation. The
term supercomputer itself is rather fluid, and the speed of today's
supercomputers tends to become typical of tomorrow's ordinary
computer. Supercomputer processing speeds are measured in floating
point operations per second or FLOPS.
 An example of a floating point operation is the calculation of
mathematical equations in real numbers. In terms of computational
capability, memory size and speed, I/O technology, and topological
issues such as bandwidth and latency, supercomputers are the most
powerful, are very expensive, and not cost-effective just to perform
batch or transaction processing. Transaction processing is handled by
less powerful computers such as server computers or mainframes.
The Blue Gene/P supercomputer at Argonne National
Lab runs over 250,000 processors using normal data
center air conditioning, grouped in 72 racks/cabinets
connected by a high-speed optical network

14. Computer By Function
 Computer are four types according to their functionalities.
 Servers
 Workstations
 Information Appliances
 Embedded Computers

15. Servers
 Server usually refers to a computer that is dedicated to provide a service. For
example, a computer dedicated to a database may be called a "database
server―.
 "File servers" manage a large collection of computer files. "Web servers"
process web pages and web applications.
 Many smaller servers are actually personal computers that have been
dedicated to provide services for other computers.

16. Workstations
 Workstations are computers that are intended to serve one user and may
contain special hardware enhancements not found on a personal computer.

17. Information appliances
 Information appliances are computers specially designed to perform a specific
user-friendly function —such as playing music, photography, or editing text.
 The term is most commonly applied to mobile devices, though there are also
portable and desktop devices of this class.

18. Embedded computers
 Embedded computers are computers that are a part of a machine or device.
Embedded computers generally execute a program that is stored in non-volatile
memory and is only intended to operate a specific machine or device.
 Embedded computers are very common.
 Embedded computers are typically required to operate continuously without
being reset or rebooted, and once employed in their task the software usually
cannot be modified. An automobile may contain a number of embedded
computers; however, a washing machine and a DVD player would contain only
one.
 The central processing units (CPUs) used in embedded computers are often
sufficient only for the computational requirements of the specific application
and may be slower and cheaper than CPUs found in a personal computer.