One of the key protocols of the Internet is the Internet Protocol (IP); alongside TCP it formed TCP/IP, which are/were the original and core protocols of the Internet protocol suite. Each device which connects to the Internet (through a computer network using the Internet protocol suite) is assigned an IP address. An IP address is a numerical address which is similar to a telephone number (a number which is assigned to a device located at a physical location).
An IP address is - in machine terms - is a binary number; but for humans to more easily process, it is defined as a 32-bit number consisting of four units. The units in an IP address are referred to as octets: which is a unit of digital (in computing) data that contains 8 bits (4x8=32 bits).
While the 32-bit version of an IP address is still in use - it was outlined from Internet Protocol Version 1 - 4 - the exponential increase of the use of the Internet is exhausting the IP addresses available. The Internet Assigned Numbers Authority (IANA) - who control the assignment of IP address block - was fundamental in suggesting that the number of bits in an IP address needed expanding. This has resulted in a 126-bit IP address model being launched in subsequent versions of the Internet Protocol.
IP addresses: In Use
The typical IP address will look somewhat like the following:
IP addresses can be either static or dynamic: typically a website will have a static IP address; as the website owners will host the service on a specific server. End-users who connect to the Internet through an ISP are typically assigned a new/dynamic IP address everytime they connect to the Internet. Dynamic IP addresses are usually assigned by a service provider from a catalog of IP addresses; so, there will be a set limit to the number of possible IP addresses that the user can be assigned.
The IP address system is part of the larger TCP/IP protocol suite: which is basically the backbone software protocol which runs and is the Internet. Without the IP address system, the Internet could not function. The DNS system is used to translate and locate domain name via an IP address assigned to them. The IP address is generally not used to locate web site addresses - by end-users - due to them being hard to remember.
End-users can attempt to hide and change their IP addresses through connecting to a proxy server. This means that the user will connect to the Internet through another computer and use it's IP address. This is useful for users who have concerns about their privacy, and, or, are subject to censorship by their Internet Service Provider. However, it should be noted: that users can still be potentially traced through their use of proxy servers.