IP2 is a very small utility that allows you to determine the IP address of your computer, both on the local network and the WAN IP address. This means that backgammon with a "traditional" IP address where your computer is accessible in your local network environment (local network), you will also be shown an IP address where your network connection is visible from the Internet.
This distinguishes this program from many other utilities widely available everywhere on the Internet, which simply show your local address, which is completely useless in case you need to know the IP address where you can connect to your computer "from outside" (for games, remote control, etc.).
Sometimes the WAN address and local IP address are the same. This can be if your computer is connected to the Internet via a dial-up connection or a cable modem and does not use a hardware NAT router. But if you use any router or other equipment to access the Internet on all your machines on the local network, your computer will most likely have a local IP address that is not accessible from the Internet. Usually such an address looks like 10.1.2.3 or 192.168.1.2. And then it is not so easy to find out your real address, which is visible to all Internet users. And in that case, the IP2 utility will help you.