WEEK 1-2: COMPUTER BASICS
· Computer Overview
Computer is an electronic device that takes raw data
as input from the user and processes these data under the control of set of
instructions (called program) and gives the result (output) and saves output
for the future use
It can process both numerical and non-numerical
(arithmetic and logical) calculations.
Computer
has four main functions:
a) Input data
b) Process data
c) Store data
d) Output data
· History
of Computers
· Type
of computers
v Since the advent of the first computer different types
and sizes of computers are offering different services.
v Computers can be as big as occupying a large building
and as small as a laptop or a microcontroller in mobile & embedded systems.
There
are four basic types of computers which are:
a) Super computer
b) Mainframe Computer
c) Minicomputer
d) Microcomputer
A. SUPERCOMPUTERS
v These are the most powerful computers in
terms of performance and data processing
v
These
are specialized and task specific computers used by large
organizations.
v These computers are used for research and exploration
purposes, like NASA uses supercomputers for launching space
shuttles, controlling them and for space exploration purpose.
v The supercomputers are very expensive and very large
in size.
v It can be accommodated in large air-conditioned rooms;
some super computers can span an entire building.
v In 1964, Seymour Cray designed
the first supercomputer
Supercomputers are used in:
a) Space Exploration: Supercomputers are used to study the origin of the
universe, the dark-matters.
b) Earthquake studies: Supercomputers are used to study the Earthquakes
phenomenon. Besides that supercomputers are used for natural resources
exploration, like natural gas, petroleum, coal, etc.
c) Weather Forecasting: Supercomputers are used for weather forecasting, and
to study the nature and extent of Hurricanes, Rainfalls, windstorms, etc.
d) Nuclear weapons testing: Supercomputers are used to run weapon simulation that
can test the Range, accuracy & impact of Nuclear weapons
B. MAINFRAME
COMPUTERS
v Super-computers are the fastest computers with large
data storage capacity, Mainframes can also process & store large amount of
data.
v Although Mainframes are not as powerful as
supercomputers, but certainly they are quite expensive
v Mainframe computers can be accommodated in large
air-conditioned rooms because of its size.
C. MINICOMPUTER
v Minicomputers are used by small businesses &
firms.
v Minicomputers are also called as “Midrange Computers”
v These are small machines with not as processing and data
storage capabilities as super-computers & Mainframes
v These computers are not designed for a single user
v Individual departments of a large company or
organizations use Mini-computers for specific purposes.
D. MICRO-COMPUTER
v Desktop computers, laptops, personal digital assistant
(PDA), tablets & smart phones are all types of microcomputers.
v The micro-computers are widely used & the fastest
growing computers.
v These computers are the cheapest among the other three
types of computer
v The Micro-computers are specially designed for general
usage like entertainment, education and work purposes.
v They are designed for use by one person at a
time.
v Well known manufacturers of Micro-computer are Dell,
Apple, Samsung, Sony & Toshiba.
v Desktop computers, Gaming consoles, Sound &
Navigation system of a car, Notebooks, PDA’s, Tablet PC’s, Smartphone's,
Calculators are all type of Microcomputers.
· Hardware parts of computer (Input,
Output, Processing, and Storage)
· Software parts of computer(System and
application software)
What
is computer software?
Computer
software: Is any set of
machine-readable instructions that directs a computer's processor to
perform specific operations
Types
of software
a) System software
b)
Application
software
System Software: Is a term referring to any computer software which
manages and controls the hardware so that application software can perform a
task
Manages the computer’s resources, enables the various
components of the computer to communicate, runs application software, and makes
the hardware respond to the user’s needs.
System software includes four main types:
1.
The operating system: provides
an interface between the computer hardware and the user or the application
software. The operating system has two primary functions:
a)
First,
it manages the computer's resources (the computer's hardware and any external
devices). For example, the operating system controls the CPU, accesses RAM,
executes programs, receives input from the keyboard or other input device,
retrieves and saves data to and from secondary storage devices, displays data
on the monitor, and controls the printer.
b)
Second,
the operating system contains instructions for running application software.
2.
Language translators: convert
application programs and any other software programs into the machine language
that actually controls the computer's operations.
3.
Network and communications software: operates
the communications hardware in a computer so that it can transmit and receive
information from other computers
Network and communications software requires two types
of software: software for the PC operating system and software for
the network operating system. In some cases, the latter comes built-in the
former.
4.
Utility programs: perform various specialized "housekeeping"
tasks, such as file management, virus protection, disk defragmentation, program
installation and uninstallation, file and disk back up, disk formatting, and
providing screen saver programs. The user directly controls most utility
programs, although some utility programs can be set to run automatically (e.g.;
screen savers and anti-virus scanning).
The system software for a single-user PC is not nearly
as complex as the system software for a multiuser mainframe computer. However,
many of the features once found only in mainframe and minicomputer systems have
been incorporated into PCs.
Application
software: Is software that
enables the user to direct the computer’s processing system in the tasks of
manipulating and transforming input data into useful output information.
v
This
is the type of software with which most users interact.
v
It
is the usual interface between user and computer.
v
Rarely
do users directly manipulate systems software, especially the operating systems
software.
v
Application
software can be either specific purpose or general purpose software.
· Computer impacts and applications.
Computer
Application
v An
aid to management: The computer can also be used as a
management tool to assist in solving business problems.
v Banking:
Branches are equipped with terminals giving them an online accounting facility
and enabling them to information as such things as current balances, deposits,
overdrafts and interest charges.
v Industrial
Application: In industry, production may be
planned, coordinated and controlled with the aid of a computer.
v Engineering
Design: Computer help in calculating that all
the parts of a proposed design are satisfactory and also assist in the
designing.
v Meteorology: Data
is recorded at different levels of atmosphere at different places, using remote
sensors carried on a satellite.
v Air
Travel: Small computers are installed as a part of the
plane's equipment.
v Road
Traffic Control: Computers assist with the control
of traffic lights.
v Telephones: Computerized
telephone exchanges handle an ever increasing volume of calls very efficiently.
v Medicine: Computers
are widely used in hospitals for such task as maintaining drugs, surgical
equipment’s and linen, for payroll and also for checkup and treatment of
diseases.
v In
addition computers are also used for recording and film studios, research,
military, etc.
Computers have both positive and
negative impact in our daily life as well as in our social life.
Positive Impact of Computer
v The work can be done in very less time.
v More information can be stored in small space.
v Multitasking and multiprocessing capabilities of data.
v Easy to access data.
v Impartiality.
v Documents can be kept secret.
v Error free result.
v It can be used for various purposes. i.e. It can be used in any type of
work.
Negative Impact of Computer
v Highly expensive.
v Accidents.
v Data piracy.
v Increased Unemployment.
v Huge data and information can be lost sometimes.
v Fast changing computer technology.
v Service distribution.
