Telecommunication & Networking - Local Area Network (LAN) Definition

Local Area Network (LAN) is a computer network that supplies networking capability to a group of computers in close proximity to each other such as in an office building, a school, or a home. It is useful for sharing resources like files, printers, games or other applications. It often connects to other LANs, and to the Internet or other WAN. 

Most LANs are built with relatively inexpensive hardware such as Ethernet cables, network adapters, and hubs.A LAN can also be configures as a ring, in which each computer is connected to two neighbouring computers to form a closed circuit, or a star, in which each computer is linked directly to a central computer and only indirectly to one another. 

Each of these has advantages, though the bus configuration has become the most common.
Even if only two computers are connected, they must follow rules, or protocols, to communicate. For example, one might signal "ready to send" and wait for the other to signal "ready to receive".

Source: global.britannica.com
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