Welcome to hn.org. At this site you can get dynamic dns free from the cloud.
What is dynamic dns?
Dynamic dns enables you to give your home computer a name that can be used from anywhere on the internet, despite having an ip address that changes.
You could name your computer hodor.hn.org, or my-pi.hn.org, or anything else ending in ".hn.org."
Actually, you have 5 pools to choose from: *.hn.org, *.home.hn.org, *.base.hn.org, *.a.hn.org, and *.b.hn.org.
So if someone already took the name hodor.hn.org, you could take hodor.home.hn.org instead.