I'm a beginner, still in school. I'm doing a small project in MFC. It's a basic animation of a ball bouncing off the four wall in a square. I don't exactly understand what this does randomly : srand((unsigned)time (NULL)). Also how would I use this to make the ball bounce randomly on the walls? Sorry if this is simple. Right now it bounce SE to SW to NW to NE. Once it hits the corners the ball then bounces across from corner to corner stuck that way.