Networks can be as simple as two computers connected together with two Network Interface Cards (NICs), to a network interconnected with Metropolitan Area Networks MANs) and various Wide Area Networks (WANs). To make it interesting you can throw in various Satellite Based Networks (SATNETS).

To be quite honest with you - we have basically just described the "Internet" in a simplistic way. The Internet is often referred to as a "cloud" because by it's very nature it defies finite description. The Internet Cloud is a virtual tangle of interconnected networks that interact with a set of rules (called Protocols). Without a defined set of rules governing interoperability and equipment compatibility standards - the Internet as we know it would be impossible to navigate, much less communicate with.

Metropolitan Area Networks (MANs) are essentially defined as a network that is constructed of hardware elements and cabling (be it fiber-optic or copper) that is installed and configured to cover a defined portion of a given Geographic Area within a Metropolitan Area, City or Town.

Note: The major difference between a WAN(Wide Area Network) and A MAN (Metropolitan Area Network) is basically semantics. A MAN generally covers a specific geographical area within a defined Metropolitan area. A WAN generally is configured to service a specific geographic region and may even extend beyond National and Inter-national Boundaries.