Inverted index

An inverted index is like a big list that helps you navigate a library. Think of it like having a library with lots of different books about different topics. For example, you might have one book about cats and another about dogs. In an inverted index, the list would show you where each book about cats and dogs is located in the library. That way, if you're looking for a particular book about cats, you can just look up the category in the list and see where it is. This saves you time because you don't have to look through all of the books in the library to find the one you're looking for!