Pomodoro timer

Twenty-five minutes of focus, then five off, and after four rounds a longer break of fifteen. The timer moves between the blocks by itself and chimes at each change, so you never have to reset it.

Francesco Cirillo named the technique after a tomato-shaped kitchen timer in the late 1980s, and the specific numbers matter less than the two rules people skip. The first is that a Pomodoro is indivisible: if you break off halfway, that round did not happen. The second is that the break is mandatory — its purpose is to make the next round possible, and skipping it is why people find the technique stops working after a day. Twenty-five and five are a starting point, not doctrine; plenty of people do better on fifty and ten once they have the habit.