These holes are called craters. Many of them are impact carters which are formed between 3000 and 4000 million years ago when meteorites and asteroids hit the surface of the moon. Some of them are pretty big up to 130 miles in diameter others are only a couple of feet. By the way, the earth had probably as many craters but water and our atmosphere have been wearing them over the last millions of years.

That's a good question!It turns out all of those "holes" are really just big dents from when other things in space have crashed into it.

The earth has an atmosphere which, aside from making it possible for us to live here, protects us from these things. Most things from space that come close to hitting the earth burn up in our atmosphere. The moon doesn't have an atmosphere, so there's nothing to protect it. Also, since there is no wine or water on the moon, there's nothing to make these craters wear away, so they stay as pronounced as the day they were formed.