Network

A Network is a communication between two or more devices. A computer network is a communication between two or more computers .This communication is build up through communication medium. A communication medium can  be  radio waves, wires, infrared, optical fibers etc.Computer networks have added a new dimension to the 21st century. Today the cyber world is much faster and wider than the real world. This all has been made possible due to computer networks. Computer networks have revolutionized the technology,business and many other matters.Computer network plays important role in our daily lives because of the very important reality that is of communication.  Computer networking is basically used to share resources like  printers, modems, files,fax machines,cameras etc between different users. Besides this, computer networks  are used for database server, computer server, email, chat, internet etc. The computer to which the resources are attached is called the server and the other computers that can access these  resource are called clients.  The sharing of fax machines, printers, and modems among many computers and users  has reduce the operational cost. So, there is no need of separate devices for each user.  A database on a computer network is a very important application as it stores and runs many important data and informations. Computer networks can supports instantaneous communications that include Email and chat among users. Computer networks also facilitate the users to send  files on a computer network.

Generally the computer networks are classified  according to the size of network or area covered by a network. Such as Local Area Networks (LAN), Wide Area Networks (WAN), Metropolitan Area Networks (MAN) and Personal Area Networks (PAN). These networks work in different topology states. The topology  is the way in which the computer networks and network resources are connected with each other. These topologies of the network can be classified as Bus Network, Ring Network and Star Network.The hardware of computer networks mainly  consists of wiring, network cards  and a hub. Purpose of Computer network cards is to maintain  understanding between computers so that one computer can  understand the talk of other computer. Each computer on the network is identified through unique address of network card. Hubs connect all the computers in the network. Hubs can also be used to connect to other hubs to increase the size of the computer network. Wires are also used to connect all computers in the network.
The number of cables increases as the number of computers in an office or a home increases. This creates complexity in wiring. This problem is solved by  wireless networking .  Wireless networking works on radio waves. In wireless networking trans-receivers or infrared signals are used to communicate between computers and devices. Examples of wireless networking include Bluetooth and Wi-Fi.  Although the wireless technology has greater benefits than wire technology but there are certain security issues involved with wireless networking. However, the demand of wireless networking is increasing among the users rapidly.