What is the difference between static and dynamic IP addresses?

When a computer uses the same IP address every time it connects to the network, it is known as a Static IP address. In contrast, in situations when the computer's IP address changes frequently (such as when a user logs on to a network through dialup or through shared residential cable) it is called a Dynamic IP address.

Static IP addresses are manually assigned to a computer by an administrator, either through the operating system configuration or through a command (e.g. ipconfig or ifconfig). This contrasts with dynamic IP addresses, where an IP address is automatically assigned to a computer by a remote server which is acting as a Dynamic Host Configuration Protocol (DHCP) server. Even though IP addresses assigned using DHCP may stay the same for long periods of time, they are liable to change depending on the addresses available in the set scope.