IP
termnetworking
Stands for: Internet Protocol
The best-effort, connectionless delivery layer that addresses and routes packets across interconnected networks, the thin waist every internet application stands on.
IP does one job and refuses the rest: it gives every host an address, routes each datagram hop by hop toward it, and fragments packets to fit each link, but it promises nothing about order, duplication, or arrival. That deliberate minimalism, formalized in RFC 791 (September 1981, edited by Jon Postel), is what let the internet scale across wildly different networks; reliability was pushed up to TCP and left out entirely by UDP. The design traces to Cerf and Kahn's 1974 paper, and its addressing is the 'IP address' the whole world now quotes.
Also known as: IPv4, Internet Protocol