What an IP address is
An IP (Internet Protocol) address is a unique numeric identifier given to a device connected to a network. It works like a mailing address for data, telling routers where to deliver each packet and where it came from. Without one, two machines cannot exchange traffic.
Why it matters
Every website visit, email, and video stream depends on IP addresses. When you load a page, your device sends requests from its IP and the server replies to that same address. IP addresses also support security and analytics, because services can see the rough geographic location and network behind a connection.
Versions and format
There are two main versions in use:
- IPv4, written as four numbers like
203.0.113.42. - IPv6, written as longer hexadecimal groups to support far more devices.
Addresses can be public (reachable from the internet) or private (used only inside a local network). For example, your home router might have a public IP from your provider while your laptop holds a private one like 192.168.1.5. You can check your current public address using the WhatIP my-ip tool.