Each time Scratch Cat reaches the green button he resets back to his start position and the timer starts again. His last recorded time to reach the green button is displayed as "Last Time" and his best recorded time is displayed as "Best Time".
This game uses the basic built-in Timer function (available in Sensing blocks) and records the time using Variables. It uses the default display of these variables by just ticking the box next to them in the toolbox. There are lots of ways that you could extend or improve this basic timer function.