What is an IP Address?
IP addresses are used to uniquely identify every host (also known as a network node) on a TCP/IP network. They are virtual addresses assigned by routers. Each of the four 8-bit fields is represented by a decimal number ranging from 0 to 255. IP addresses are typically owned and controlled by a DHCP server running in the local network's router. Devices requesting to join a local network could be assigned any available local IP address, and the assigned IP address could change at any time.
As a side note, the IP address examples shown here are IPv4 addresses. IPv4 is still used for the vast majority of internet communications, but it will eventually be replaced with IPv6 which uses eight 16 bit fields of addressing.
IPv4 allows 4.3 billion addresses (about one per person)
IPv6 allows 3.4 x 10 to the 38 addresses (5 x 10 to the 28 addresses per person)