How to use the online timer
Hours are for the things that cannot be hurried. A chicken in the oven, a shoulder of lamb at a low temperature, a turkey for a gathering, dough proving somewhere cool, a full gym session, a shift, a long drive broken into legs, a paper written against exam conditions. At this length the count is not there to be watched — it is there so nothing has to be remembered.
Two practical points matter more at this scale than any other. The device has to stay awake for the whole stretch, since a sleeping laptop takes the countdown with it, so plug it in and stop the screen switching off. And with anything cooking for hours, temperature settles the question at the end rather than the clock, which only tells you when to go and check.