introduction of network

A network is a collection of computers and device   connected together via communications devices and media.

A modem is an  example  of a communications devices.

Example of communications media are cables, telephone , lines cellular radio and satellites.

Some of  these media, such as satellite and cellular, radio are wireless  which means they have no physical lines or wires. When your computer connects to a network, you are considered online.

Networks allow users to share resources, such as hardware devices, software programs, data and information.

 Sharing  resources save time and money.

For example  , instead of purchasing one  printer for every computer in a home, you can connect a single and all computers  via a network.

This type of network enables all the computers to gain access of the same printer.

Most businesses network their computer together. These networks  can he relatively small or quite extensive.

A  local  area  network (LAN) is  a network that connects computer in a limited geographic area.

Such as a school  computer laboratory, office or a group of buildings.

A wide area network(wan) is a network that covers a large  geographical area, such as one that connects the district offices across the country.


The world’s largest network is the internet.

The internet is world wide collection of network that links  together millions of businesses, government agencies, educational institutions and individuals with an abundance of resources and data  accessible via internet, more than  360 million users around the world are making use of the internet for variety of reasons.



Need for networking

Hardware sharing:-

   In a networked environment, each computer on a network can access and use hardware that is too costly to provide  for  each user or cannot be justified for each user because the equipment is used infrequently.

For example  supposing there are area number of personal computers on  a network and each requires the use of a laser printer. If the  personal computers and the laser printer are connected to  a network, each personal computer user can access the laser printer over  the   network. Each personal computer user can access the laser printer over the network as he/she needs it.

Data and information sharing –

In a  networked  environment, computer on a network can access and use a  computer on a network to access data and information stored on other computers in the network.


computer on a network environment,  computer on a network can access and  use a computer on a network to access data  and information stored on other computer in the network.

A large company , for example , might store a data base of customer a modem to connect to network, can access this  data bases  

Software sharing:-

  With software sharing , frequently is stored on the hard disk of a server hard disk so that multiple users on the network can access the software.

To  support software sharing, most software vendors sell network version of their software.

When  we purchase a network version of software package, software vendors  issue a legal agreement called a site-licensee, which allows many users to run the  software package.

The site license fee usually is based on the number of users or the number of computers attached to the network.

Sharing software VIN a network usually costs less than buying individual copies of the software package for each computer.

As with data and information sharing, software sharing also requires  the capability of sharing  hardware resources, such as  space on the hard disk of the server..