IP addressAn IP address, also called a logical address, uniquely identifies a node on the network. IP stands for Internet Protocol. It is by following this protocol, that machines worldwide, are able to move data between networks and have it end up at the right machine. Just as a complete mailing address helps to ensure that the ordinary mail you send will arrive, a complete IP address will help you contact the site you want to reach.
The IP address consists of a 32 bit binary number. Because such a number would be hard to read, it is broken up into a four part decimal number, each section representing 8 bits of the 32 bit address. Each address includes a network number, a subnetwork number, and a host number. If you look at many IP addresses from the same large site, you will normally find that the network number is the same, and all of the subnetwork and host numbers are taken from a predetermined range.
An IP number, is not be confused with a URL. The IP number is designed to help you locate a machine, whereas a URL, as its full name indicates, is a Uniform Resource Locator, will take you to the particular page or file that you want to access.
Users who access the WWW from a SLIP/PPP connection may notice that their host number varies from session to session. This is because the local network dynamically assigns a host number when a SLIP/PPP user logs onto the network, and this number is taken from a range of host numbers available to that subnetwork.