What is an IP address?
A number that identifies a device on a network.
Every device that talks on the internet needs an address, so data knows where to go. That's an IP address.
What it is
An IP address is a number that identifies a device on a network. The classic kind, IPv4, is four numbers from 0 to 255, separated by dots.
How it works
Data travels in small packets, each labeled with where it's going and where it came from. Routers pass each packet one hop closer. There are only about four billion IPv4 addresses, so a home usually shares one public address, and the devices inside get private ones. IPv6 has vastly more.
Why it matters
It's how a server knows where to reply, and how firewalls decide what to let in. DNS exists so you can type a name instead.
