chronography

Chronography is the practice or science of recording and presenting time. It covers the documentation of temporal sequences, the construction of chronological charts, and the graphic portrayal of time intervals. Etymologically, the term derives from Greek chronos, meaning time, and graphein, meaning to write.

In horology, chronography refers to the measurement and recording of elapsed time. A chronograph is a timekeeping device—often a wristwatch or pocket watch—that can start, stop, and reset a separate timing mechanism while the main display continues. Subdials or digital readouts show elapsed seconds, minutes, and sometimes hours. Chronographs are used in sports timing, aviation, and scientific experiments, and many watches include tachymeter scales to compute speed over a fixed distance.

History and development: The first practical chronograph was developed in the early 19th century by Nicolas Mathieu Rieussec, around 1821, to time horse races and record moments with ink on a dial. Over the 19th and 20th centuries, mechanical and then electronic versions evolved, leading to the modern wrist chronograph. The term remains common for devices that can measure and display elapsed time, as opposed to simple timekeepers.

Other uses: In historical writing and data visualization, chronography can refer to the graphic representation of time—timelines, chronological tables, or time axis diagrams—that organize events in sequence. In this broader sense, chronography intersects with chronology and related methods for dating and ordering events.