What exactly does the term "voter suppression" mean?

In 2020, at my place of voting all I had to do was walk in, give them my name, they find it in a book, I sign my name on the line in the book, then I go to the booth to vote.

I think I read about them wanting us to show photo ID. I'm actually surprised we don't have to show photo ID. Closing the voter places earlier just so certain people can't vote, is wrong.