Functions & Complications
A watch can do considerably more than simply display the hours, minutes and seconds. Additional functions range from practical features such as displaying the date or a second time zone to highly complex mechanisms capable of measuring elapsed time or representing astronomical information.
This section explains watch functions and complications, including chronographs, GMTs, calendars, moonphases, power-reserve displays and more advanced horological mechanisms. It also explores the terminology used to describe how these functions operate and how they are displayed.
Glossary terms
ChronographA watch with an integrated stopwatch function that can start, stop and reset elapsed-time measurement.
ComplicationAny watch function beyond the basic display of hours, minutes and seconds.
CountdownA watch function or complication known as Countdown, adding information or capability beyond basic time display.
DateA watch display showing the numerical day of the month.
Day IndicatorA watch function or complication known as Day Indicator, adding information or capability beyond basic time display.
Day-DateA watch display showing both the day of the week and the numerical date.
Dual TimeA watch function that displays two time zones simultaneously.
Elapsed Time BezelA watch function or complication known as Elapsed Time Bezel, adding information or capability beyond basic time display.
GMTA function that displays a second time zone, usually with an additional hand read against a 24-hour scale.
GPSA watch function or complication known as GPS, adding information or capability beyond basic time display.
Hacking FunctionA watch function or complication known as Hacking Function, adding information or capability beyond basic time display.
Hand-Winding FunctionA watch function or complication known as Hand-Winding Function, adding information or capability beyond basic time display.