Chapter 1: (Topic 2 - Part 1) What is computer and what does it do?

Chapter No 1: Introduction to the world of computers

Topic 2 (Part 1) : What is computer and what does it do?

A computer can be defined as a programmable, electronic device which is capable of receiving information (data), performs operations on that data, presents the results, and stores the data or results in the form of information or signals as needed. The fact that a computer is programmable means that a computer will do whatever the instructions called the program tell it to do.

Computer

OR

A programmable, electronic device that accepts data input, performs processing operations on that data, and outputs and stores the results.

OR

In the easiest form, computer is an electronic device, which receives instruction from user, process it, gives outputs and save results. 

Block diagram of computer

Input: The process of data entering into the computer

Process: Performing operations on data that has been input into a computer to convert that input to output.

Process cycle

Output: Process of presenting the results

Storage: Saving data, programs for future use

Overview

Overview

Features of the computer

Today, computer is the most demanding machine in the world because of following features:

(1) High Speed

(2) Accuracy

(3) Large Storage capacity

Data vs. Information

Data (Raw, uncategorized facts) may be in the form of letter, the numbers in a monthly budget, the images in a photograph etc… when data is processed into a meaningful form, it becomes information. The conversion of data into information called Information Processing. Information processing is a very important activity today for all computer users, as well as for businesses and other organizations. 

Types of computers

There are several types of computers out there. Here’s a very short description of most common ones. Computers are generally classified in one of six categories, based on size, capability, and price.

1. Embedded computers

These computers with tiny shapes embedded into products to perform specific functions or tasks for that product. They often embedded into home appliances (such as microwave, coffee makers, DVD players, TVs). 

Embedded computer

2. Mobiles

Mobile phones and other personal pocket size devices that contains built in computing capabilities. Mobile devices used for to make a telephone calls, send text messages, browsing WebPages, take digital photos, download music or movies and other so many features. 

Smart phones

3. Personal computers (Microcomputer)

A type of computer based on microprocessor used by a one person at a time. A laptop or a notebook is a lighter and more portable version of PC that can run on batteries.

Personal computer (Desktop computer)

4. Midrange servers

Those computers who host data and program available to the small group of users calls midrange servers. A server is a central computer where users on the network can save their files and informations.

Midrange servers

5. Mainframe computers

Those powerful computer who used to host a large amount of data and programs available to a vide group of users. 

Mainframe computer

5. Super computers

These are extremely powerful computers used for complex computation and processing. A supercomputer comprised of numerous smaller computers connected together to act as a single computer.

Super computer