A computer network is a communications network that connects a collection of different or similar types of computers and networks to allow communication and data exchange between systems, software applications, and users. The computers that are involved in the network that originate, route and terminate the data are called nodes, and each have a unique location identity. The interconnection of computers is accomplished with a combination of cable or wireless media and networking hardware devices.
Two devices are said to be networked, when a process in one device is able to exchange information with a process in another device. Networks may be classified by various characteristics, such as the media used to transmit signals, the communications protocols used to organize network traffic, network scale, network topology, benefits, and organizational scope. The best known computer network is the Internet.
Communication protocols define the rules and data formats for exchanging information in a computer network. Well-known communications protocols include Ethernet, a hardware and link layer standard that is widely used for local area network, and the Internet protocol suite (TCP/IP), which defines a set of protocols for communication between multiple networks, for host-to-host data transfer, and for application-specific data transmission formats. Protocols provide the basis for network programming.
Computer networking may be considered a branch of electrical engineering, telecommunications, computer science, information technology or computer engineering, since it relies upon the theoretical and practical application of the related disciplines.
A computer network has the following properties:
- Facilitates interpersonal communications
- People can communicate efficiently and easily via email, instant messaging, chat rooms, telephone, video telephone calls, and video conferencing.
- Allows sharing of files, data, and other types of information
- Authorized users may access information stored on other computers on the network. Providing access to information on shared storage devices is an important feature of many networks.
- Allows sharing of network and computing resources
- Users may access and use resources provided by devices on the network, such as printing a document on a shared network printer. Distributed computing uses computing resources across a network to accomplish tasks.
- May be insecure
- A computer network may be used by computers Hackers to deploy computer viruses or computer worms on devices connected to the network, or to prevent these devices from accessing the network (denial of service).
- May interfere with other technologies
- Power line communication strongly disturbs certainforms of radio communication, e.g., amateur radio. It may also interfere with last mile access technologies such as ADSL and VDSL.
- May be difficult to set up
- A complex computer network may be difficult to set up. It may be costly to set up an effective computer network in a large organization.
Great...Great...Great 