What Is Computer Network
Computer network systems usually connect two--or more than two--computer networks for communication, file sharing, and data sharing purposes. Computer devices such as printers, scanners, and hubs can also be shared across networks. Computer users can connect to a network system inside their homes, across the street, down the block, across country, and even around the world.
Local Area Network
A LAN, or local area network, is a connection of computer system within a building or offices close together. Local area networks can be as broad as connecting computers within a public school district, or as small as linking multiple computers inside a household. LANs are inexpensive compared to the other types of network systems and can use either wired or wireless connections. LANs operate within a relatively small area, but they can connect to larger network systems and greatly expand their reach.
Wide Area Network
A WAN, or wide area network, covers an entire geographical area, such as a state, region, or entire country. A wide area network can be self-contained, but always connects with other LAN and MAN network systems (see next section for explanation of MANs). WANs utilize expensive computer networking equipment and are operated by large telecommunications companies and large corporations that need to share a network in a specific area. For instance, a large pharmaceutical chain would use a WAN to gather prescription information from their customers. A customer would fill a prescription from one location and--through a WAN--their information can be transferred to any other store, worldwide.
Metropolitan Area Network
A MAN, or metropolitan area network, is a connection of two or more local area networks. Many local area networks within cities are often linked to a metropolitan area network through a high-speed Internet connection, such as one that runs over fiber-optic cable. Cable television providers or government entities operate metropolitan area networks. MANs can act as significant links between smaller local area networks and much larger wide area networks.
Storage Area Network
A SAN, or a storage area network, is a variation of a local area network. The purpose of a storage area network is to store large amounts of data, which can then be transferred at a high rate of speed. Businesses commonly use storage area networks. Multimedia companies often benefit from using a SAN, because they need to store large amounts of data for video editing.
