A second is a unit of time that is widely used in everyday life and scientific measurements. It is defined as the duration of 9,192,631,770 cycles of radiation corresponding to the transition between two hyperfine levels of the ground state of the cesium-133 atom. This precise definition helps ensure consistency in timekeeping across the globe. In practical terms, a second is a small interval, with 60 seconds making up a minute and 3,600 seconds in an hour. Clocks and watches measure time in seconds, allowing people to coordinate activities and schedules effectively. The concept of seconds is essential in various fields, including physics, sports, and music.