Computer Networks

What is Computer Network ?

Definition : The computer network can be defined as a group of computers and other devices (such as printers, scanners, routers) connected together in order to send or receive data.

* Each of these devices in the computer network is called node. In computer network each node is connected by a wire through which the data can be moved in the form of electromagnetic waves. However there is another terminology which is commonly used in computer network and i.e. host. The host is synonym to the computer node, however there is one clear difference between node and host. Node refers to any device on the computer network and host refers to the fully functional general-purpose computer.

Components used in Networking :

* A computer network comprises the following components :

1. A minimum of at least 2 computers.

2. Cables that connect the computers to each other, although wireless communication is becoming more common.

3. A network interface device on each computer. This is called a networking interface card  or NIC.

4. A 'Switch' used to switch the data from one point to another.

5. Network operating system software.

6. You can create a computer network by hooking all the computers in your college together with cables and installing a special network interface card (an electronic circuit card that resides inside your computer popularly called as NIC) in each computer so you have a place to plug in the cable. Then you set up your computer's operating system software to establish networking. 

* Each node in the network has some unique address. These addresses help to identify the computer quickly. Addresses are assigned differently on different kinds of networks. These addresses are assigned by the organizations that are setting up the corresponding network. Typically these addresses are numeric that is easy for computers to work with,  but not for humans to remember.

Examples : 192.168.0.165

Some networks also provide names that human can more easily remember than numbers.