An IP address, short for Internet Protocol address, is an identifying number for a piece of network hardware. Having an IP address allows a device to communicate with other devices over an IP-based network like the internet.
What is an IP Address Used For?
An IP address provides an identity to a networked device. Similar to a home or business address supplying that specific physical location with an identifiable address, devices on a network are differentiated from one another through IP addresses.
If I'm going to send a package to my friend in another country, I have to know the exact destination. It's not enough to just put a package with his name on it through the mail and expect it to reach him. I must instead attach a specific address to it, which you could do by looking it up in a phone book.
This same general process is used when sending data over the Internet.