Internet Protocol address. The address of a computer on a TCP/IP (Transmission Control Protocol/Internet Protocol) network. IP addresses are written as four groups of up to three digits (eg, 169.237.104.18).
A computer on the Internet is identified by its IP address. In order to avoid address conflicts, IP addresses are publicly registered with the Network Information Centre (NIC). Computers on private TCP/IP LANs however do not need public addresses, since they do not need to be accessed by the public. For this reason, the NIC has reserved certain addresses that will never be registered publicly. These are known as private IP addresses, and are found in the following ranges:
From 10.0.0.0 to 10.255.255.255
From 172.16.0.0 to 172.31.255.255
From 192.168.0.0 to 192.168.255.255
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http://www.vicomsoft.com/glossary/addresses.html
http://en.wikipedia.org/wiki/IP_address