The movement, or inner workings, of a watch are what make up the main timekeeping mechanism. This mechanism measures the passage of time and displays the current time and other information including date, day and month. These movements can be entirely mechanical, entirely electronic or a combination of the two.
Mechanical movements, such as hand wound or automatic watches require winding in order to run. An automatic watch uses the force of gravity to constantly wind itself. Automatic watches have a greater consistency of power and therefore can be more accurate.
An electronic watch employs the use of a tiny quartz crystal that vibrates in the presence of electricity. This type of watch is powered by a battery and its time is regulated by the tiny quartz crystal. This is why most electronic watches are also called quartz watches. Solar powered watches convert energy from light into electricity which is then stored in a rechargeable battery. These watches do not need to have the battery replaced as long as they are regularly exposed to a fairly strong light source.
Kinetic powered watches use a combination of mechanical and electronic elements. Usually a weight rotates with the motion of the wearer's arm which turns a generator to supply power. It is similar to an automatic watch except that electrical power is generated by the mechanical motion.
The crystal is the protective cover on the face of the watch. A crystal can be made out any material that allows the face to be seen. The most common crystals are made of glass, acrylic or synthetic sapphire. Acrylic crystals are made from a plastic composite that is generally less expensive than glass or synthetic sapphire crystals. Glass crystals are hard and difficult to scratch but can shatter, while a synthetic sapphire crystal can be shatter-resistant and nearly scratch-resistant.
The bezel is the surface ring that surrounds and holds the crystal in place. It can be made out of almost any metal. On many luxury watches the bezel may contain diamonds or gemstones, while on sportier models the bezel may have calibrated markings on it and rotate in a unidirectional manner.
A complicated watch is any watch that features one or more utilities beyond the basic function of displaying the time and date. The two most popular complications are chronograph and moonphase. Chronograph is the ability of the watch to function as a stopwatch, and moonphase displays the phases of the lunar cycle. Many calendar types are considered to be complicated.
Calendars can appear in many different forms on a watch, from the basic date display to a more evolved design displaying the day, date, month, year and moonphase. For many watches, these functions need to be adjusted slightly to account for fewer days in a month or leap year. However, a perpetual calendar feature will automatically adjust to account for lengths of months (28 to 31 days) and leap years. Watches with perpetual calendars are usually powered by quartz or mechanical movements are programmed to be accurate until the year 2100.
Watches come in many different shapes and styles. Most watches will fall into three main categories; casual, dress, and sport watches.
Most watches feature some type of resistance from water. This is determined based on the amount of water that the manufacturer has successfully tested their product in. The amount of water that these watches can withstand is rated in depths, ranging from 30 meters (100 feet) to 200 meters (660 feet). Below is a listing of each level of water resistance and a description of the amount of water they typical can withstand.