This page opens with the timer already set to 10 minutes. Press Start or hit the spacebar and it begins; when time is up the alarm rings and the disk blinks. You can always drag the disk to a different time.
For short bursts, a shape beats digits. A 10-minute disk tells you what's left in one glance, so you keep moving instead of checking a clock.
Use a 10 minute timer for vocabulary review, a quick morning workout, or capping meeting talk time.