An Internet Protocol (IP) address is a numerical label that is assigned to devices participating in a computer network that uses the internet protocol for communication between its nodes. The IP address served two main purposes – it provides a way for a node (e.g., computer or device) to be uniquely indentified within a network that it belongs to and it also acts as an address, which means that the IP address provides information about where the node is and how it can be reached.
An IP address has been originally defined to be composed of a 32-bit number which allowed for many possible IP addresses. However, with the explosion of network-connected devices and growth of the internet, the limit set by using a 32-bit number for IP address has been slowly reached and resulted in the depletion of IP addresses. This prompted the standards body that oversees the internet protocol to device a new addressing system that uses 128 bits for the address.
There are two main types of address – public and private. A private IP address belongs to a group of IP addresses that has been specifically reserved for use in private networks. Public IP addresses are assigned to computers and devices that are connected directly to the global public internet. Network address translators connect devices with IP addresses to the public internet. The allocation of public IP addresses is managed by the Internet Assigned Numbers Authority (IANA). IANA cooperates with Regional Internet Registries to allocate blocks of IP addresses to local internet service providers and other entities.