No need to apologize for asking questions, I like to think the good people here at Zelaron enjoy answering them. Roughly, sprites are images placed onto other images on the screen ( like the images of characters in a game placed over backgrounds) . RM2k3 is "free" because it was illeagally translated by Don Miguel. As for the RMXP 30 day trial, you must have downloaded the official version otherwise it too would have been "free." Hope that helps, good luck making games.