This chapter gives a brief overview of the history and development of tools for finding and measuring time, from those used in ancient Egypt through to the development of the mechanical pendulum clock. Particular emphasis is placed on short-interval timing and how, in practice, the instruments used were not necessarily horological. The Earth's rotation and the resultant apparent motion of the Sun across the sky formed our basic concept of time and served as the principal time standard, against which all clocks and tools of time measurement were calibrated, until it was supplanted by atomic timekeeping in the late 1960s. Two key constituents of the atomic clock, electricity and the quartz crystal oscillator, are referenced in the concluding section as part of a discussion about the role of the stopwatch in science and why, despite its ubiquity in the laboratory, the stopwatch goes largely undocumented in science writing.