Every computer on the internet has a unique IP address that identifies it to other computers on the internet. IP addresses are pretty much like a phone numbers. In the same way that a phone number identifies a caller to other phones, computers use IP address to identify themselves to other computers on the internet. Because all of the computers on the Internet conform to the same sets of rules and standards, they can all communicate with each other in the same network. The rules and standards that enable all of the computers to communicate with each other are grouped in a protocol called TCP/IP. According to the TCP/IP protocol, each computer should have a unique IP address in order to be able to transfer data on the internet.
An IP address can be dynamic or static. Most IP addresses are dynamic, and they are assigned automatically to computers by their internet providers. Dynamic IP address means that the IP of the computer changes from time to time because it has a limited lease time of hours to months. When the lease expires, the internet provider will automatically assign a new IP address to the computer. Static addresses are pretty rare and are created and maintained by IT experts for companies or businesses that have a special need for a constant IP address.