Computer | Computing Fundamental

Introduction

Computer Science is about problem solving and developing algorithms to solve complex problems.

Computer Science is the study of the theoretical foundations of information and computation.

It also includes practical techniques for their implementation and applications.

What is a Computer System?

A Computer System is a device that works according to the following systems :

It is capable of performing computations and making logical decisions.

It is a machine that can transform data into useful information.

It processes data under control sets of instructions called computer programs.

What is Computation?

Computation is any type of calculation or use of computing technology in information processing .

Computation is a way of describing information processes (Language).

Computation is a way of predicting properties of information processes (Logic).

Types of Computing

Type

Details

Personal Computing

Economical enough for individual use.

Distributed Computing

Means by which a single computer program runs on more than one computer at the same time.

Client/Server Computing

Sharing of information across computer networks between servers and clients (personal computers).

Advantages of Computer Science

Computer Science has several advantages:

It is the fastest medium of communication (much faster than postal mail or telegraphic communication).

Through computers, text messages or images can reach any part of the world using internet.

Arithmetic problems can be easily solved with a computer.

Through video conferencing one can not only see but also talk with anybody living in any part of the world.

Computers make it possible to receive, supply and process large volumes of data at very high speeds.

Computers greatly improve the speed of:

Data Input

Data Output

Data Processing

Data Transmission

How Computers Work?

A Computer is an electronic machine that:

Accepts information and stores it until the information is needed.

Processes the information according to the instructions provided by the user.

Ultimately returns the result to the user.

Use of Computers

Computers are used in:

Scientific calculations

Commercial and business data processing

Space guidance

The educational field and many others

Types of Computers

Personal computer, Tablet, Smartphone

Workstation

Minicomputer

Main frame computer

Super computer

Personal Computer, Tablet, Smartphone:

A small, single-user computer based on a microprocessor

Workstation:

A powerful, single-user computer

A workstation is like a personal computer, but it usually has:

A more powerful microprocessor

A higher-quality monitor

Mini Computer:

A multi-user computer capable of supporting up to hundreds of users simultaneously

Mini Computers are used in:

Universities

Research Organizations

The Government Sector

Mainframe:

A powerful multi-user computer capable of supporting many hundreds or thousands of users simultaneously

Main Frame Computers are used in:

Industries

Banks

Airlines

Supercomputer:

An extremely fast computer that can perform hundreds of millions of instructions per second

Super Computers have applications in:

Research

Massive data-processing applications

Nuclear and plasma physics

Space research

Digital Computers

Digital Computers follow sequences of instructions called programs that operate on given data.

Users can specify and change programs and/or data according to their specific needs.

Types of Digital Computers:

General-purpose digital computers:

PCs

Specific-purpose digital computers:

Telephone switching exchanges

Digital voltmeters

Frequency counters

Calculating machines

Computer Organization

Computer Architecture

Part

Use

Input

Obtains information from input devices (keyboard, mouse).

Output

Outputs information (screen, printer).

Memory

ROM (Read Only Memory)

RAM (Random Access Memory)

Arithmetic Logic Unit

Part of the CPU (Central processing Unit)

performs arithmetic calculations (addition) and logic decisions

Control Unit

Part of the CPU (Central Processing Unit)

controls the flow of information

Hardware and Software

Computer is a combination of Hardware and Software.

Hardware includes physical parts of computer:

CPU, Keyboard, Mouse, Printer, Modem and Scanner, Speaker, Microphone and Camera

Software includes an interface between the user and the computer.

OS (Operating Systems):

Win 7, Win 8, Linux, UNIX, Mac OS X

Computer Languages:

C, C++, Java

Computer Application Programs:

MS Office, AutoCAD, Photoshop

Operating System

Software that manages computer hardware

Controls all machine activities

Provides the user interface to the computer

Manages resources such as the CPU and memory

Examples:

Windows, UNIX, Mac.