Watch - ancient mechanism. Watches are mechanical and electrical. Watches are big or small, for example: narusnye watches and cuckoo clocks, which weigh on the towers - Glockenspiel. So there is a sundial, water clocks, fire clocks, hourglass, clock radio, quartz watch. Water, sand and fire watch is not a clock in the usual sense, since they do not show the current time.
