Umm.. where to start?.. Ok.. I was writing a program using the SDL library.. and tried to print out the score (int score) to the screen using drawString(...).. it kept giving me errors cannot convert, etc.. the same thing is when you try to output numbers using windows' MessageBox().. then I read a tutorial and found this: drawString(...,...,"Score: %d",score); .. and it worked.. what exactly does the %d do there and what other stuff like that there is that I don't know (I bet it's C stuff..)?