The meaning of a computer network

There are many advantages that can be obtained by using a computer network, including the following:

1. It helps to share resources from one computer to another becomes easy. This saves time that could be used to send information from one person to another.
2. It helps to reduce administrative costs. For example, the use of a networked printer helps to share it with other computer users who are in the same network.
3. It helps computers to share software. This reduces the cost of purchasing software for every individual personal computer. For example, buying a computer antivirus program for each computer is expensive.
4. It helps to save data or information in different locations to ensure data security.
5. It helps to improve communication. For example, the use of email in public and private offices, business industry, education and in other areas which provide social services.
6. It helps to reduce the cost of purchasing paper, printing and information or data transfer.
7. It helps to improve efficiency of individuals and institutions in general.

Computer networks are classified in various ways. Geographical area is one of the aspects used to classify computer networks. There are many types of computer networks commonly in use. In this section you will learn about two most popular types of computer networks. These networks are

1. Local Area Network (LAN)
2. Wide Area Network (WAN)

This is a type of network that connects computers which are located in a small geographical area. LAN connection can be done in a single room, office, school building, home or laboratory. Also, LAN can connect its network devices using wires, without using wires or both forms (wired and wireless) at once. An individual person, school, company or institute can own a LAN. The use of this type of network is specifically for people in the same small area where that network operates. For example, a company or organization employees and college or school communities use LAN connections

1. Easy to run and administer because it is located in one area.
2. LAN devices are abundant in the market and are cheap.
3. Simple to share files and folders.
4. Easy to administer a security policy to protect network users.
5. It provides the opportunity to store publications for shared use, for example using servers to facilitate sharing of database.
6. Network computers can share operating and application software. This helps to save the cost of buying software and installation for every client's computer.
7. Central back-up can take place automatically at regular intervals.

1. It covers only a small geographical area.
2. It is easy for hackers to have unauthorized access to the system programs and threaten the security of user information.
3. When the server crashes or gets technical faults, all users are affected.
4. It is easy for viruses to spread throughout the LAN system and affect all client computers.
5. It needs skilled personnel to install and administer a LAN

A company or organization may start with a small branch having few offices. This branch can be installed with a LAN to operate its activities and communication depending on the workplace. Later, the organization or company may grow and expand its services to other new areas. For example, branches may expand from one town to another, one region to another or outside the country. When new branches are opened, Local Area Networks need to be installed to improve company's services.

These new branches may need to communicate or have connection with their headquarters in order to share information, data and monitor employees' performance. The computer network which is formed when LANs from different branches communicate with each other over the network, is known as Wide Area Network (WAN). Therefore, WAN is a computer network that connects computers over a large geographical area such as country, continent or the world.

Example of WAN network

1. Extends its scope of communication throughout a wide geographical area.
2. Allows sharing of application software and other resources from different locations.
3. Provides online access to national and international trade markets.
4. Provides fast and secure communication to all national and international online users.

1. WAN has low security compared to LAN.
2. The cost of setting up a WAN is much higher than a LAN.
3. Running cost of WAN is high.
4. WAN requires a software program for prevention of users' data or information from hackers.