IPaadress

An IP address (Internet Protocol address) is a numerical label assigned to each device connected to a computer network that uses the Internet Protocol for communication. It serves two main functions: identifying the host or network interface and providing a location address that can be used for routing packets across networks. IP addresses can be assigned to devices by a network administrator or an Internet service provider, and they often change over time due to DHCP and network address translation.

There are two main versions: IPv4 and IPv6. IPv4 addresses are 32-bit numbers, typically written as four decimal octets separated by periods, for example 192.0.2.1. IPv6 addresses are 128-bit numbers, written as eight groups of four hexadecimal digits separated by colons, for example 2001:0db8:85a3:0000:0000:8a2e:0370:7334. IPv4 uses subnet masks or CIDR notation to define networks, e.g., 192.168.1.0/24. IPv6 uses prefix lengths, e.g., 2001:db8::/32.

Addresses can be public or private. Public addresses are reachable on the Internet; private addresses are used inside private networks and are not routable on the public Internet. Network Address Translation (NAT) often maps private addresses to a single public address. Devices can obtain addresses dynamically via DHCP or use static addresses.

Typical special addresses include the IPv4 loopback 127.0.0.1 and the IPv6 loopback ::1, and private ranges such as 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16 for IPv4. IP addresses play a central role in routing and network management, and their allocation and configuration are governed by standards and regional Internet registries.