Millisecond (ms)
The millisecond, symbol ms, is one-thousandth of a second. It is important to time very short periods. The millisecond, a unit of measurement in the metric system, is used in science, computers, and engineering. It measures speeds and response times in digital devices. People’s reaction times are often measured in milliseconds, making it useful in medicine, sports, and psychology. Its accuracy helps capture events that happen too fast for the eye to see.
Second (s)
The second is the fundamental SI unit used to measure time. At first, it was defined as 1/86,400 of the average length of a solar day. However, because the Earth’s rotation is not perfectly consistent, this method was imprecise. In 1967, scientists redefined the second based on atomic properties: one second equals the duration of 9,192,631,770 cycles of radiation from a cesium-133 atom. This atomic standard ensures remarkable accuracy in timekeeping, which is essential for technologies like GPS, communications, and scientific experiments. The second remains a cornerstone for tracking and organizing time in today’s world.