A watch is composed of three essential parts :
- The movement is the set of mechanisms serving to indicate the hour, minutes, seconds, fractions of a second, date…
- The dial and hands are the organs serving to display the time
- The case protects the watch movement. Composed of the middle, bezel, glass and back, it gives the watch its style and personality.
A simple mechanical movement generally comprises some 130 parts (a part being any individually-made element, e.g. a wheel is a separate part to a pinion.Movement size is measured in millimetres. Watchmakers also measure in lines where one line ("') equals 2.255 mm.