An IP address ( Internet Protocol address ) is a unique number that devices use in order to identify and communicate with each other on a computer network utilizing the Internet Protocol standard ( IP ). Any participating network device — including routers , computers , time-servers, printers, internet fax machines, and some telephones — must have its own unique address.  An IP address can also be thought of as a street address or a phone number but for a computer or other network device on the internet. Just as each street address and phone number uniquely identifies a building or telephone, an IP address can uniquely identify a specific computer or other network device on a network.