Altimeter: This feature measures the altitude of an object above a
fixed level, such as sea level.
Calendar: This feature, which can be found in analog and digital
watches, displays the day and date in a given month on the watch's dial
face.
Chronograph: A chronograph is a specific type of watch that combines
stopwatch functionality with a typical display watch.
Luminous: A watch with luminous features can be read at night or other
low-light situations.
Water Resistant: A watch that is water resistant has been tested to
resist damage due to water at specific depths. The water resistance level is
often marked on the dial or caseback.
Compass: A compass is a navigational instrument that measures
directions in a frame of reference, such as the cardinal direction points of
N,S,E and W.
Depth Measurement: This instrument, mostly found in dive watches,
measures depth beneath a fixed level.
GPS: GPS instrumentation is essentially a space-based satellite
navigation system that provides location and time information.
Heart Rate Monitor: Mostly found in sport and active watches, this
instrument measures the wearer's heart rate.
Moon Phase Calendar: This calendar function, which is an ornamental
display often found in dress watches, chronicles the phases of the moon
throughout a given month.
Screw-Down Crown: This crown type, which is commonly found in dive
watches, screws into the side of the case via a special tube to lock out debris
and water.
Shock Resistant: This feature is a common mark stamped on the back of
wrist watches to indicate how well a watch copes with mechanical shocks. A watch
described as "shock resistant" has survived a series of shock tests.
Stopwatch: This functionality is designed to measure the amount of
time elapsed from a particular time when the device is activated to when the
device is deactivated.
Tachymeter (Tachometer): This functionality is designed to measure
revolutions per minute.
Timer: A timer is simply a specialized mechanism designed to measure
time intervals.
