The point is you can mix them, and vary the results of the animation, but I agree that you don't need both, just the best value for _DELAY would do as well. I usually just use _LIMIT to reduce CPU usage in keyboard input loops, but it was fun to use it in this animation, well, until some party pooper came along, that is. In this example, lowering the frames rate below 10 will change the animation speed, although I do agree just adding to the delay would achieve much the same results. If it was a loop for a much longer use, like most video games, I would certainly want to limit the frames rate to save CPU usage. For this example, the _LIMIT could be removed and the results, with the smaller delay, would be comparable. Basically I just introduced a new QB64 statement to the user, but it isn't introducing it at its best. I hope he does know that he can use various delays like .12, .104, etc., up to 7 digits. That gives a lot animation potential.
So as for what the commands do, I know what they are for. Now go be a dear and find some of those "many" examples, so I can have a look at them.
Pete