I was here.
"________ was here" carved in a tree or a bathroom stall is a lot like the Voyager Golden Records.
Voyagers 1 and 2 still soar through space to explore beyond our solar system. The peaceful messages in different languages and media are there in case alien life discovers it. Each message is simple and each is a mark to show that people exist. It's a way of saying, "I am here."
A meaningful message can be a funny thing.