Using the background() command as the first line in the draw() function, it will "erase" the screen, and your drawing will appear to be animated.
Create a program that places a large colored dot in a random location on the screen, and then move it to a new location. Use the frameRate() command to draw at 2 frames per second (the lower the number in the frameRate(), the slower the animation).
You need: stroke, StrokeWeight, point, background() and frameRate functions.