A stopwatch is a handheld timekeeping device that is used to measure the time elapsed between two points in time. It typically includes a start/stop button and a reset button. Stopwatches can be used for timing various events, such as sports competitions, cooking, and more. The time measurement can range from milliseconds to hours. Mechanical stopwatches have a rotating dial and an exposed mechanism that displays the time elapsed. Digital stopwatches use electronic components to measure and display time. Some stopwatches also include additional features such as lap timers and alarms.

Stopwatches can be used in many other applications that require accurate and precise time measurement.

The first stopwatch was invented in the late 19th century by Louis Moinet, a French watchmaker. He created the stopwatch to accurately time astronomical events. The concept of the stopwatch was later developed further, and it became widely used in sports and other timing applications. Today, stopwatches are widely used in various fields, including sports, education, industry, and science, and they come in various types, including digital, analog, and multi-functional.

There are various types of stopwatches including manual, mechanical, quartz, and digital. Manual stopwatches require manual winding, while mechanical and quartz stopwatches run on springs and batteries respectively. Digital stopwatches display the time on an electronic screen and can have added features like a countdown timer and multiple time-recording capabilities. Stopwatches are used in a wide range of applications including sports timing, scientific experiments, industrial timing, and everyday timekeeping. They are commonly used to time events in sports, such as running races and swimming competitions. In education, stopwatches are used to time reactions in science experiments and in industry, they are used to time production processes and work tasks. The features of stopwatches vary depending on the type and model. Some stopwatches have multiple time-recording capabilities, while others have a lap-splitting function. Some stopwatches can be synchronized with external timing devices, and others have countdown timers and alarms. Stopwatches have evolved over time with advancements in technology. From the early manual stopwatches to the modern digital stopwatches, the basic design remains the same but with added features and improved accuracy. The advent of electronic and digital technologies has made stopwatches more accessible and user-friendly.