Do you completely forget the book or is it just not at the top of your mind?

I read a lot and for a few weeks I can remember a lot of details about each book I read, but then they kind of move lower in my memory. If someone asks me about the book if I see the cover or read a bit of the book summary I will recall a lot more details of the book, but some of it will just be lost over time.

This is the same with movies I watch, TV shows I watch, interactions I have with people etc. My husband says his brain is like a computer hard drive, you can only store so much on it or it starts to slow down, so we forget things that aren't important to us.