Guess What I am Thinking?

I have talked to myself but not out loud, continuously, every day, all my life. I have never asked if other people do this too. If everyone does this, it is a big subject. The voice inside my head that is talking, I think of it as thinking. What else could it be? Because if it is not thinking, then what could think be? A pal?

1200px-Le_Penseur_in_the_Jardin_du_Musée_Rodin,_Paris_14_June_2015