The various types of movements
Before examining the various types of movements, it may be relevant to explain what is the movement of a watch. This designates all the parts constituting the mechanism which makes the watch work and which creates units of time (seconds, minutes, …).
There are two main families of movements: mechanical movements and electronic quartz movements.
Watch enthusiasts appreciate mechanical movements the most: they find them more noble than quartz movements in spite of their imperfections.
All mechanical movements feature at least one system for storing energy during winding. This system, called barrel, utilizes a spiral spring which is being compressed during winding and which gradually releases the stored energy, which in turn makes the watch work.
The difference between automatic winding mechanical movements and manual winding ones pertains to the way the spring of the barrel is compressed.
For manual winding mechanical watches, as its name indicates, the manual rotation of the crown compresses the spring. For automatic winding mechanical watches, the motion of the wrist will move an oscillating weight around which will compress the spring by rotating around its axis.
Manual winding mechanical watches need to be winded regularly - often on a daily basis. Automatic winding mechanical watches only require manual winding on restart: automatic winding takes over afterwards while you are wearing the watch.
Once the winding is over, how long the watch will function depends on the model and ranges from 12 hours to several days - the average being about 40 hours. This duration, called power reserve, is the time required for a watch “at rest” to consume all the energy stored in the barrel.
It is important to note that a mechanical watch only works in an optimal way when the movement is fully winded. In such circumstances, the parts of the caliber are appropriately set in motion and your watch is consequently more accurate. When the power reserve is low, the energy level is low and the watch get increasingly less accurate until it stops.
The precision of mechanical watches is rather variable and depends on a number of parameters: quality of the movement components and quality of the configuration. Drifts vary between +/- 6 seconds per month and +/- 10 seconds per day.
ELECTRONIC QUARTZ MOVEMENTS
Electronic quartz movements are less prestigious than mechanical movements but are cheaper and more accurate.
The heart of an electronic quartz movement is made of an integrated circuit. The watch works thanks to a battery which energy makes a quartz oscillator vibrate.
The lifecycle of a battery can last up to several years during which no intervention is necessary on your watch - except a potential water resistance check.
It is also worth noting that some automatic quartz watches store the mechanical energy from the motions of the wrist and convert it into electrical energy.
Quartz watches have two display modes: analog display - with hands - and digital display. In the latter case, no need for mechanical transmission: impulses are directly transmitted from the integrated circuit to the liquid crystal screen.
These two display modes are sometimes combined to provide you with a variety of information.
The main benefit of quartz watches is that they are extremely precise: their daily drift is about +/- 0.3 seconds per day.