When you are reading, do you hear words in your head?

I like to read but on one hand I don’t think I’m a good reader, and on the other hand I don’t know what constitutes a good reader.

My sister, who reads a ton of books (fiction), says she hears the words when she reads and each character has a different voice. I read books sporadically and don’t hear the words, it’s more like I absorb the content (if that makes any sense).

So what say you? Do you hear words when reading? Do you just absorb the content? Or is there something else?