What's your IP? Your IP is: 18.104.22.168
IP stands for Internet Protocol, the rules that defines how Internet communication works. When you say "What's your IP?" you are meaning what's your IP address. Address is omitted.
Every http request is sent with an ip address, which is used from the server to send back the answer. The HTTP protocol is an asycronous protocol, that is to say that there isn't a permament connection between the two systems talking. The client make a request, the server receive the request and send back an answer, the informations are sent through Internet and there isn' a permament channel between client and server.
This tool allows you to discover your IP address which is the address of your device on the Internet. If you're in an office network or there many computers connected to your wifi router the IP is shared with the other devices of your same local network.
If you need to find a tool to discover your ip address to configure a firewall rule you are in the right place. This is a free tool to find your ip address.
Geolocate a device with the IP address
As you wait some seconds after the load of the page you will see other data appearing. These data includes geolocalization from your IP address. The IP addresses are geographically distributed with a defined hierarchy, so by mapping the numbers to countries and regions it's possibile to extrapolate the geographic position of your device. But as you can see it's not really precise.
This page was made using Minibots PHP class which gives you some bot-super-powers like free geocode functions and more. If you want to discover more about Internet protocols you can start from Wikipedia with its page on Internet Protocol.