What a 1 hour timer is for
An hour is the standard block for a lesson, a meeting, slow cooking or a study session. The page loads with the countdown already set, so the whole interaction is one click.
The timer runs on the browser clock, not a server, so it works offline once the page is open and it keeps counting in a background tab. At zero it plays a short chime; keep the tab unmuted if you plan to walk away.