An IP (Internet Protocol) address is a unique identifier assigned to each device connected to a computer network that uses the Internet Protocol for communication. It serves two primary functions: host or network interface identification and location addressing. There are two main versions of IP addresses in use:

1. IPv4 (Internet Protocol version 4): This is the original and most widely used version. An IPv4 address consists of 32 bits and is usually represented in decimal format as four numbers separated by periods (e.g., 192.168.1.1). Each number can range from 0 to 255. Due to the limited number of IPv4 addresses, a new version was developed.
2. IPv6 (Internet Protocol version 6): This is the most recent version, designed to replace IPv4. IPv6 addresses are 128 bits long, allowing for a significantly larger number of unique addresses. They are typically represented in hexadecimal format, separated by colons (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334).

IP addresses are fundamental for the functioning of the internet, enabling computers to send and receive information to and from specific locations in the network. They are crucial for routing traffic and ensuring that data reaches its intended destination correctly.