This tells about what it is. It's a notation that tells where things are on the chess board. So if you wanted a specific board setup you could use it. In this program it's not exactly correct, and it only uses the first part.
@XanthusPettitt Ooo I was just looking at your profile, are you making it in python? and are you making it only using the terminal?? I love that idea.
Yeah chess is a lot more complicated than I thought is what I learned while making this game haha. Make sure you find all the little rules and try to implement them. But start with the basics