Introduction to Computer Notes-9

Introduction to Computer 

The modern world is called the age of science and technology. We cannot imagine life without science and technology. The modern world of advanced technology could not have been established without the development of computer technology. There is rapid development in computer. Computer is used in many different fields for varieties of tasks. It is used all over the world, no matter whether a country it is developed, developing or underdeveloped. Computer is also used in Nepal various fields like: business, bank, education, entertainment, scientific research, law, airlines, traffic control, etc. So, the computer is now affecting every sphere of human activities and leading to many changes. It has brought enormous changes in the world.

Introduction

The word "Computer" is derived from the Latin word "Computare" which means 'to calculate'. Nowadays, computer has become an indispensable part of our life. Computer is used in various places like: home, school, college, offices etc. Computer can perform complex mathematical calculations accurately in a short period of time. The modern computer has lots of capabilities like creating documents, videos, games, music presentation, etc. It can use AI (Artificial Intelligence) for understanding natural language, taking self-decision capabilities, analysing graphs and patterns, etc. 

Data is raw facts, concepts, or instructions in a formalized manner, which should be suitable for communication, interpretation, or processing by computer. Data is represented with the help of characters such as alphabets (A-Z, a-z), digits (0-9) or special characters (+,-,/,*,<,>,= )

Information is organized or classified data, which has some meaningful results for the receiver. Information is the processed data or meaningful results on which decisions and actions are based.

What is a computer?

A computer is an electronic device that accepts raw data and instructions from users; processes it according to the given set of instructions, stores and gives meaningful information.

Working Principle of a Computer

Computer is an electronic device that converts raw data into meaningful information carrying out various processes as instructed by the programme. Every computer has the ability to: 

a. Input: Enter raw data into the computer. 

b. Process: Process according to the given set of instructions to produce the required result. 

c. Output: Get meaningful information from the computer.

 d. Storage: Store data and information for future use.

Characteristics of a Computer 

A computer is powerful and useful in all areas. The use of computer is increasing with time. The main features or characteristics of computer are described below:

i. Automatic

A computer is an automatic device. It can do tasks automatically as instructed by software. It can automatically control various devices attached with computer system.

ii. Speed

A computer performs tasks accurately. The operations on data in computer are performed through electronic circuit according to given instructions. Computer can perform millions and billions of operations on data within a second. The speed of computer is measured in MegaHertz (MHz) or GigaHertz (GHz). The time taken to perform a task is measured in fraction of second. The smaller units of second are given below: 

Unit of Time             Meaning                                     Part of Second                    Power of 10 

Millisecond (ms)       One thousandth of second        1/1000                                  10-3sec. 

Microsecond(us)        One millionth of second           1/1,000,000                          10-6sec. 

Nanosecond(ns)         One billionth of second            1/1,000,000,000                   10-9sec. 

Picosecond (ps)          One trillionth of second          1/1,000,000,000,000              10-12sec. Femtosecond (fs)      One quadrillionth of second    1/1,000,000,000,000,000       10-15sec.

iii. Accuracy

 A computer performs t4asks accurately. If data and instructions given to the computer are correct then it gives an accurate output. It means output totally depends on the given instructions and input data. If input data is incorrect then the output will be incorrect which is called GIGO (Garbage in Garbage out).

iv. Storage

Computer system consists of data storage unit. A computer has main storage and secondary storage. A large amount of data can be stored in secondary storage like hard disk, pen drive, CD/DVD, etc. for future use. The main memory (RAM) stores currently used data. Computer stores data in term of 0 and 1. The different units of storage in computer are given below:

S.No.        Memory Unit        Description 

1                  Bit                       1 Bit = 0 or 1

 2               Nibble                   1 Nibble = 4 Bits 

3                Byte                      1 Byte = 8 Bits

4            Kilobyte (KB)         1 Kilobyte (KB) = 1024 Bytes

5        Megabyte (MB)           1 Megabyte (MB) = 1024 KB 

6        Gigabyte (GB)             1 Gigabyte (GB) = 1024 MB

7       Terabyte (TB)                1 Terabyte (TB)= 1024 GB

8        Petabyte (PB)                1 Petabyte (PB) = 1024 TB 

9       Exabyte (EB)                1 Exabyte (EB) = 1024 PB 

v. Diligence

 A computer can continuously work for a long time without losing its speed and accuracy. So it is called diligent device. It doesn’t get tired or bored or lazy while working.

vi. Versatile 

A computer is a versatile device which means it is flexible. It has capability of performing different types of tasks like drawing paints, playing games, music, calculations, sending an e-mail, desktop publishing work, etc. in different field efficiently. So it is used in different fields to perform varieties of tasks.

Application of Computer 

A computer is given great importance in every field of work. Nowadays, it is impossible to find where computer are not used. Computer and its technology are used in education, agriculture, industries, banking, engineering, scientific research and many more. The main applications of computer are described below: 

i. Education

Nowadays, computer and Internet technology have changed the present education system. Computer technology can be used for visual illustration like smart classroom and distance learning education system. Today, school and colleges use computer in computer lab and multimedia to teach students. A teacher can teach by using computerbased presentations. Students can study various subject and complete assignment by using Internet.

ii. Communication A computer plays a key role in the field of communication. The Internet and computer are used to send and receive information. A computer uses various communication services like e-mail, video conferencing, net phone, chatting, Facebook, Twitter, Instagram, etc. 

iii. Banking Sector

A computer has brought revolution in the banking sector. The different services like accounting, customer records to update, bank statement etc. are performed by using computer in banking sector. ATM (Automated Teller Machine) allows 24 hours banking services to their customers so that they can withdraw money at any time.

iv. Medicine 

A computer is used in scanning and diagnosing of various diseases through CT scan (Computed Tomography scan), ultrasounds, ECG (Electro Cardio Graph) etc. It is also used in hospitals to keep records of patients and medicines. Nowadays, computer is used in surgery too. Doctors use computer and Internet services to provide telemedicine services to remote areas of our country, Nepal.

v. Entertainment

 A computer is used to entertain people. It is used to play games, listen to music, watch videos, movies and cartoons etc. It is used to watch online movies and play online games.

vi. Scientific Research 

A computer is used in all types of scientific research. Scientists collect the latest information by using internet all over the world. It is used in weather forecasting, space research, complex research in various scientific fields etc.

vii. Agriculture 

Computer has not only made changes in modern occupation but also made changes in the traditional occupation sector like agriculture. Through the social networking site, farmers can get connect with other experts and exchange their views and other details when they have internet connected computers. Farmers can get information on different agricultural issues through internet surfing. Farmers can get connect with foreign customer which can help to improve their product and increase their production capacity. Farmers can use the computer to keep financial record, production record, online banking, online sales, onlne purchased the required resources through the internet. The amount of water sprinkled in a balanced quantity can also computerized.