Is it normal to have other people/voices in your head?

There's sort of two people in my head. They don't have names or genders, though I think one is male and one is female, but they've been in my head for as long as I can remember. One of them is kind of mean while the other is like a "guide" or something. I'm not talking to myself, these people aren't me. They don't have bodies they're just voices, some times they can control me too. It's complex sitiustion I cannot firmly explain in full meaning, but I hope anyone who reads gets it.