Watches bring a fascinating array of functionalities through carefully constructed complications, each unique in its own way. So you must know what means what in the watch market; else, you might cheat yourself off a good buy.

1. Audible Alarm – Alarm functions in expensive watches. They ring both by default and user-set patterns. A few good recommendations will be the Citizen Campanola Grand Complication Chime, the Citizen Minute Repeater Eco Drive Perpetual Calendar or the Citizen Attesa Eco-Drive.

2. Chronograph – Any watch with an ability to perform as a stop-watch. These often have extra dials denoting, day, date or some other function. Some good examples are the Seiko Flightmaster and the Citizen Eco-drive Chronograph Super Titanium.

3. Moon Phase – Displays the waning/waxing of moon; the lunar phase. Check out the Seiko Premier Kinetic Direct Drive and the Citizen Eco-Drive Moon Phase.

Citizen Eco-Drive Moon Phase BU0011-63ZB
Citizen Eco-Drive Moon Phase BU0011-63ZB

4. Tourbillon – A device countering the gravity and improving accuracy in time-keeping. Tourbillon watches always come for a price, so don’t expect an Omega Central Tourbillon or Richard Mille’s RM 29 Tourbillon Nadal within the Seiko, Tissot or Citizen price-ranges. They are way up higher.

5. Perpetual Calendar – A calendar that runs and adjusts by itself; currently, most will go on till 2099. Creation watches sell some of them, like the Citizen Eco-Drive AT and the Orient Classic Automatic Multi-Year Calendar.

6. Calculator – Self contained mathematical calculator in watches. Require a digital display. See one, for example.

7. Heart Rate Monitor – Monitors heart rate during athletic workouts. The Polar Fitness Training Heart Rate Monitor Watch got to be the coolest of them all!

8. GPS (Global Positioning System) – A system that locates position (of a place, object or person) using satellite technology. The Polar Fitness Training Heart Rate Monitor Watch doubles up as one.

9. Jewel: These are the bearings inserted into pivot points inside watch movements; or easier, the tiny red or pink dots on the bridges and pillar plate of the movements. They keep the parts from coming into direct contact with the edges of the holes and stop metal from grinding against metal, stopping friction-related damages. The jewels are hard and hence, endure a lot. Certainly, today they are no more the tiny, doughnut-shaped rubies, diamonds or sapphires any more like the early days of watch-making. Some affordable names in this domain are the Bulova Automatic (also the BVA Series) and the Orient Automatic.

10. 17-jewel: It was a standard set by the American railroad system. It was necessary to include that number of jewels in a movement for precision timekeeping. Later, by the early twentieth century, conductors and engineers started using 19 jewels or more in their railroad watches. Here’s more comprehensive data.

11. Water Resistant: Only applies to watches that go by the ISO 2281 standard. It implies water resistance in common daily uses. So washing of hands or a light exposure to water is okay while swimming or diving may not be. For that, you need an ISO 6425 certified watch. To obtain that, a watch needs to:

a. Prove reliability under 30 cm of water (18 °C to 25 °C) for 50 hours.
b. Must resist the formation of condensation at extreme temperatures.
c. Must have its functionality (and hence, components) intact under pressure.
d. Water resistance at varying pressures.
e. Must withstand extreme heat.

So, when the watch reads water resistant, see how many meters it is for. 30M to 50M is okay for a low water exposure; 100M withstands recreational water sports. For professional water sports/activities, it is 200M while for scuba diving, 300M+ (sometimes with helium-safety) is usually recommended. So, buy the Citizen Eco Drive Limited Edition Atomic Perpetual Chronograph if you are to wear the watch to invitations, parties and max, pool sides; for the wilds, you need the Citizen Promaster 200M Marine Diver Solar.