What's the Difference Between a Diary and a Novel?

It is formatted like a diary. It's an epistolary novel. And so it is dated. You go through, you know, I don't know, maybe 6-8 months or 9-10 at the most. There are times where it is just like, had a bad day. Don't have much to say. Move on to the next post. She reads very fast and she reads all the time the main character does.