An IP address lookup will determine the geolocation of any IP address. The results of the IP address lookup will show you the city, state/region, postal/zip code, country name, ISP, and time zone. This data can be used by various agencies to find the exact owner of any IPv4 or IPv6 address.
It can be an app that you install, or you can just use google and type in the search box what is my IP address, and google will spit back a little box with your external IP address as well as a list of other sites.
Basically, an IP Address is a unique number consisting of four parts separated by dots. Every device on the Internet (and on any network) must have a unique IP address to participate and be part of it. An example of an IP address is: 192.168.1.1.