Time study is a technique for measuring and analyzing the time required to complete each element of a specified job under standard conditions. It involves breaking down jobs into individual elements, observing workers complete elements using a stopwatch, and analyzing the data to determine time standards. There are three main timing methods - flyback uses a stopwatch that resets between elements, cumulative records continuous time and subtracts to find element times, and differential times small elements by timing groups with and without the element. While flyback avoids calculations, continuous method provides total time and some unions prefer it to avoid potential lost time from flyback resets.