The regulating organ of a mechanical watch is the balance wheel with its spiral.

The process of setting or adjusting a clock.

Timing the movement of a clock consists of observing its daily rate at various positions and at various temperatures, then (if necessary) making fine adjustments to optimize its speed. The amount of labor invested in this task is directly proportional to the quality of the clock and its desired degree of accuracy, which, in turn, is directly proportional to its price. Accurate timing according to official procedure requires adjusting the movement in at least five positions and at three different temperatures (23.8 and 38 degrees Celsius).

One of the first additional features assigned to train clocks with mechanical gears, the first alarm mechanisms were realised as early as the 16th century. They emit an acoustic signal when a predetermined time arrives. Eterna first patented an alarm wristwatch in 1908. The most famous wristwatches with alarm clocks include the 'Cricket' by Vulcain (which premiered in 1947), the 'Memovox' by Jaeger-LeCoultre ( launched in 1951) and the 'Memomatic' by Omega (launched in 1969). The alarm time on the 'Memomatic' can be set to the exact minute.

The time is indicated by a pair of hands. The current time is indicated by the relative positions of the hour hand and minute hand. With very few exceptions, almost all high-quality wristwatches are equipped with analog time display. The digital electronic watches that dominated the market in the 70s have lost most of their importance.

Wristwatch displaying the correct date for the one-year interval from 1 March of one year to 28 February of the following year.

The astonishing work of a pocket watch or wristwatch is automatic if, unlike the astonishing work of a repeater watch, it functions completely without the need for manual intervention. Like a household clock, an automatic strike watch audibly announces the arrival of the hours (petite sonnerie) or both hours and quarters (grande sonnerie). In response to the push of a button, these elaborate mechanisms can also be activated to strike the hours, quarters and minutes.

An additional mechanism that uses the wearer's arm movements as a source of energy to wind the mainspring of a mechanical watch. Abraham Louis Perrelet is credited with the invention of the self-winding portable watch. A self-taught watchmaker, Perrelet presented two different self-winding constructions in 1770: one was based on an oscillating mass; the other on an infinitely rotating rotor. Both were designed to make the winding key superfluous. Self-winding mechanisms on pocket watches could not function efficiently because these watches do not undergo sufficient movement, so the popularity of such mechanisms remained limited. Wristwatches, which are worn on one of the most active parts of the body, helped self-winding achieve a breakthrough. The beginning of this breakthrough is attributed to the Parisian watchmaker Léon Leroy in 1922. The first mass-produced wristwatches with automatic winding were designed by Englishman John Harwood, who patented a corresponding mechanism in 1924. Rolex debuted the first wristwatch with rotor (unidirectional) winding in 1931. Felsa, the ébauche manufacturer, introduced a bidirectionally wound rotor in 1942. Eterna's ball-winding rotor, which debuted in 1948, paved the way for the self-winding systems that followed in later years. After the 'quartz crisis' had subsided somewhat, the renaissance of self-winding wristwatches began in 1983. Rolex debuted the first rotor-wound (unidirectional) wristwatch in 1931. Felsa, the ébauche manufacturer, introduced a bidirectionally wound rotor in 1942. Eterna's ball-winding rotor, which debuted in 1948, blazed a trail for the self-winding systems that followed in later years. After the 'quartz crisis' had subsided somewhat, the renaissance of self-winding wristwatches began in 1983. Rolex debuted the first rotor-wound (unidirectional) wristwatch in 1931. Felsa, the ébauche manufacturer, introduced a bidirectionally wound rotor in 1942. Eterna's ball-winding rotor, which debuted in 1948, blazed a trail for the self-winding systems that followed in later years. After the 'quartz crisis' had subsided somewhat, the renaissance of self-winding wristwatches began in 1983.