delta time makes up for games being fast by making them slower to correct the speed and make it smoother. the reason why 250fps and 60fps are extra slow is because scratch is only 30fps, which makes 30fps the correct speed. to find the delta time you find the time between the last frame and the current frame which gives you a value. if you do the [move (10) steps] block, but make it [move (10 * ("delta_time" * 30))] it does the same thing but according to scratch fps and lag to make it smoother.
