Is it a bad thing to tell someone your IP?

The IP address can be thought of as the phone number for your computer. Just as you wouldn’t hand out your phone number to any random idiot on the internet, you shouldn’t hand out your ip address. The danger is the same: harassment and/or hacking.

There are very, very few legitimate reasons for someone to need to know your IP address. Also, for most residential connections, your ip address will change over time (dynamic IP). So giving it to someone would be of limited use anyway.

Note that hosting a service, such as a game server, is one of those very few legitimate reasons. But in general, there is no need to give it to anyone.

Xyzzy, thank you. I needed to know because I am in fact, going to host a game server. So far it is working well, thank you.