12/24 Hour Format:  A digital watch having the option of displaying the time in either standard 12 hour format or 24 hour (military time) format.

Acrylic Crystal:  A crystal composed of a plastic composit that flexes instead of shattering on impact and can be easily polished if it becomes scratched. It is also less expensive and less durable than a sapphire or mineral glass crystal.

Ana-Digital or Ana-Digit:  A watch that has hands for analog timekeeping as well as a digital display in numbers.

Analog:  A watch that tells time using an hour, minute and sometimes a seconds hand.

ATM:  Atmospheres - Every 10 meters (33 feet) of water depth is equivalent in pressure to one atmosphere of air. This measurement is used to indicate the level of water resistance.

Automatic (Movement):  Most high-end watches are automatic meaning they do not use a battery at all rather they are powered off the motion of the wearer. Automatic watches generally feature a power reserve of 36 hours. A distinct advantage is the fact that automatic watches never need battery changes, but will stop running if not worn regularly or placed on an automatic watch winder.

Bezel:  The “bezel” refers to the ring around the crystal that is seen when looking directly at the face of the watch. On many luxury watches, the bezel contains diamonds or gemstones while on sportier model watches the bezel may contain calibrated markings for timing events. The bezels on the sport watches can turn in one direction, or occasionally, in either direction (see unidirectional bezel).

Bi-directional Rotating Bezel:  A bezel that can be rotated either clockwise or counterclockwise. These are used for mathematical calculations such as average speed or distance (see "slide rule") or for keeping track of elapsed time (see "elapsed time rotating bezel").

Bow:  The curved metal part at the crown of a pocket watch that allows attachment of a chain or strap.

Bracelet:  A bracelet is a strap, which uses links that are gold, silver, stainless steel, or a combination of all or any two of these materials. Bracelets generally allow for better breathing for the wearers wrist. Calendar: A feature that shows the date, and often the day of the week. There are several types of calendar watches. Most calendar watches show the information digitally through an aperture on the watch face. Some chronograph watches show the information on sub-dials on the watch face.

Butterfly Buckle:  Also called a deployment buckle. The fastener folds under the band and is hidden. The butterfly type has dual folding sides.

Cabochon:  A smooth round domed stone, either genuine or synthetic gemstone often used to decorate a watch crown.

Case:  The “case” protects the inner workings of the watch from shock and exposure to the elements. The serial number and model number may be listed on the back of the case. A typical watchcase is made out of stainless steel but can also be gold, silver, or titanium.

Caseback:  The bottom of the watch case that can be opened to replace the battery or repair the watch.

Chasing:  Decoration of the bridgework on a mechanical movement by hand or machine.

Chronograph:  A watch with subdials within the larger dial that measures elapsed time. An independent second hand can be started, stopped and returned to zero by pushers or buttons on the case.

Chronometer:  A high-precision watch capable of displaying seconds and housing a movement that has been tested to meet the ISO 3159 standard set by the Swiss Official Chronometer Control (COSC). Any watch designated as a chronometer has been individually tested and is provided with a certified movement.

Côtes de Genève:  Also called Geneva Bars, a decoration consisting of an even pattern of parallel stripes applied to the flat surfaces of the watch movement.

Crown:  The “crown” refers to the grooved knob on the outside of the watch used wind manual watches. The crown is also used to set the time and calendar date. On many sport model watches, the crown may screw down into the casing of the watch to insure waterproofing.

Crystal:  A generic term used to describe the transparent cover on a watch face. Materials used today include mineral glass, synthetic sapphire or scratch-resistant Hesalite or Plexiglas. High-end wrist watches often have a sapphire crystal which is highly resistant to scratching.

Dial:  The “dial” refers to the face of the watch and is a term usually used when referencing the color. A dial may contain smaller “sub-dials” for seconds, minutes, or hours (see chronograph).

Digital:  Displays the time on a screen in numbers.

Display:  A watch that shows the time by means of hour and minute hands (analog display) as well as by numbers (a digital display).

Dual Time:  A watch that has two dials to keep track of time in two different time zones.

Elapsed Time Rotating Bezel:  A graduated rotating bezel (see rotating bezel") used to keep track of elapsed time. The bezel can be turned so the wearer can align the zero on the bezel with the watch's seconds or minutes hand. After a period of time passes, you can read the elapsed time off the bezel. This saves you having to perform the subtraction that would be necessary if you used the watch's regular dial.

EL Light:  Electro-luminescent light. Some watches require an additional battery for this feature.

Escapement:  Device in a mechanical movement that controls the rotation of the wheels and thus the motion of the hands.

End of Battery Life Indicator:  This feature warns the wearer that the battery is running low and should be replaced. The indicator varies among different manufacturers but the most common one is on quartz watches. The second hand will start ticking in 5 second increments instead of the normal one second at a time.

ETA:  A Swiss producer of high quality mechanical and quartz movements.

Fob:  A pocket watch strap usually made of leather or the ornamental medallion used on the end of a pocket watch strap.

GMT:  Greenwich Mean Time - the standard for all international time.

Guilloche:  Decoration of dials, rotors or case parts consisting of patterns made by hand or engine-turned.

Hand:  Pointer that indicates the hours, minutes or seconds as well as other functions.

Hesalite Crystal:  A scratch-resistant crystal that is composed of a high-impact acrylic composite which if scratched can easily be polished out.

Ionic-Plated or IP-Plated:  An advanced dry vacuum plating process which is very durable, wear-resistant and bright. IPB-Plated = Ion Plated Black and IPG-Plated = Ion Plated Gold.

ISA:  A manufacturer of watch movements in Switzerland and China.

Jewel:  A synthetic ruby used for making low friction bearings in which the pivots of the movement wheels run.

Kinetic:  Kinetic is based on revolutionary technology. Kinetic watches run entirely on self-generated energy from the natural movement of your wrist. They never need a battery change.

Kinetic Auto Relay:  Like all Kinetic watches, Kinetic Auto Relay is powered by human movement. However, when it senses inactivity for three days, it puts itself into suspended animation to conserve energy. Wake it up with a few shakes of your wrist. It automatically resets itself to the exact time, even if it's been "asleep" for up to four years.

Link:  The “links” are the individual pieces that connect to form the bracelet.

Liquid-Crystal Display (LCD):  A digital watch display that shows the time electronically by means of a liquid held in a thin layer between two transparent plates. All LCD watches have quartz movements.

Louis XV Hands:  A fancy scrolled watch hand most often seen on Grandfather clocks.

Luminous:  A painted substance that absorbs light and glows in the dark which is sometimes added to watch hands and/or markers.

Manual:  A hand-wound mechanical movement.

Markers:  Dots, slashes or any decorative markings used in place of numbers on the watch dial.

Mechanical Movement:  Mechanical Movements are hand-wound. In hand-wound watches the mainspring is fastened at one end to the inner surface of the barrel and at the other end to the core. When the watch is wound, the spring is slowly wrapped around the core completely. A hand-wound watch is fully wound when the crown can no longer be turned clockwise.

Mineral Crystal:  Watch crystal made of tempered glass to increase its scratch resistance.

Moisture Resistant:  The ability of a watch to withstand rain and slight splashes of water, but not to be able to withstand full submersion.

Moon Phase:  The display of the lunar cycle (rising, full or waning moon) featured on some watches. A "true moon phase" display should not be confused with a "sun/moon" dial which only shows the sun during the AM hours and stars during the PM hours.

Mother-of-Pearl:  The iridescent interior shell of the freshwater mollusk that is sliced thin and used on watch dials and detailing. Most mother-of-pearl is white but may also be black, grey, blue or pink.

Movement:  The movement refers to how the watch operates. The movement is the mechanism that keeps the time running. Movements are either quartz, manual winding or automatic winding.

Open Heart (Cut Away) Dial:  A small portion of the dial is cut away to allow viewing of the balance wheel mechanism on a mechanical watch.

PNP Plating:  Palladium Nickel Plating - palladium (a precious metal in the same family as platimum) is combined with nickel to produce a hard, tarnish-resistant silvertone finish.

Pusher:  A button that operates the special functions of a watch.

PVD Plating:  Physical Vapor Deposition - a dry vacuum process which gives an ultra-hard corrosion-resistant finish of zirconium and titanium nitrides and comes in many colors.

Quartz:  A very accurate battery operated movement which uses a Quartz crystal to keep time.

Ronda:  A manufacturer of watch movements in Switzerland and Asia.

Rotating Bezel:  A bezel (the ring surrounding the watch face) that can be turned. Different types of rotating bezels perform different timekeeping and mathematical functions (see elapsed time rotating bezel," "unidirectional rotating bezel," and "bi-directional rotating bezel.")

Rotor:  Half disc which rotates inside the case of an automatic watch by the movements of the wearer's arm. The movements are transferred to continually wind the mainspring.

Sapphire Coated Crystal:  A mineral glass crystal that has been coated with synthetic sapphrie to improve its scratch resistance and durability.

Sapphire Crystal:  Man-made material (synthetic corundum) used for watch crystals. Sapphire crystals are scratch-proof but not shatter-proof. In general, luxury watches contain the more expensive, sapphire crystal.

Skeleton:  Case, movement and/or dial which features clear windows and cut-aways to enable the viewing of the watch mechanism.

Stainless Steel:  Metal alloy known for its resistance to rusting. There are a variety of grades of stainless steel with the most common one used for watch cases being "surgical stainless steel."

Sub-Dials:  Smaller dials within a watch dial which may indicate seconds, day, date or other features.

"Swiss Made":  In the world of watches, the word "Swiss" is synonymous with quality. But what does it really mean?  Swiss law is very specific on what points of origin and assembly are permissible in watches that are labeled "Swiss Made." In specific, the law requires that the assembly work on the movement (the motor of the watch) and on the watch itself (fitting the movement with the dial, hands and the various parts of the case) should be carried out in Switzerland, along with the final testing of the movement. It also requires that at least 50% of the components of the movement should be manufactured in Switzerland. So it is permissible for the movements in Swiss watches to contain a minority portion of parts made outside Switzerland. But the majority of movement parts must come from Switzerland and the entire movement, and watch must be entirely assembled in Switzerland. The watch casing and separate or detachable items, such as watch bracelets, do not have to be manufactured in Switzerland. But the "foreign" parts must be delivered to Switzerland unassembled, with actual assembly of them into a watch occurring on Swiss soil. Other provisions allow for watches where the movement meets the criteria, but the watch is assembled outside of Switzerland to be labeled "Swiss Movement" on the dial.

Tachemeter:  A tachymeter is the name of the scale sometimes inscribed around the rim of an analog watch. It can be used to compute speed based on travel time or measure distance based on speed. The function performed by a tachymeter is independent of the unit of distance (e.g. statute miles, nautical miles, kilometres, metres etc.) as long as the same unit of length is used for all calculations.

Telemeter:  A telemeter determines the distance of an object from the observer by measuring how long it takes sound to travel that distance. Like a tachymeter (see "tachymeter"), it consists of a stopwatch, or chronograph, and a special scale, usually on the outermost edge of the watch face.

Unidirectional Rotating Bezel:  An elapsed time rotating bezel (see "elapsed time rotating bezel"), often found on divers' watches, that moves only in a counterclockwise direction. It is designed to prevent a diver who has unwittingly knocked the bezel off its original position from overestimating his remaining air supply. Because the bezel moves in only one direction, the diver can err only on the side of safety when timing his dive. Many divers' watches are ratcheted, so that they lock into place for greater safety.

Titanium:  A stonger and lighter metal than stainless steel. Titanium never rusts or tarnishes and is hypoallerginic.

Tungsten:  A virtually indestructible metal that requires little care. The high polish surface will last for life.

Unidirectional Bezel:  This bezel can move in one direction and is used for mathematical and time past uses.

Water Resistant:  Case designed to help prevent water from entering the mechanism. Unless otherwise specified, water resistant watches can safely withstand minimal contact with water (i.e. getting splashed from the sink faucet). Most watches contain this feature. Some watches will specify that they are water resistant up to 30 meters and some may go up to 1000 meters. This means that the watch can be completely submerged up to the stated depth without damage.