A millisecond (from milli- and second; symbol: ms) is a unit of time in the International System of Units (SI) equal to one thousandth (0.001 or 10−3 or 1/1000) of a second and to 1000 microseconds. A unit of 10 milliseconds may be called a centisecond, and one of 100 milliseconds a decisecond, but these names are rarely used.To help compare orders of magnitude of different times, this page lists times between 10−3 seconds and 100 seconds (1 millisecond and one second). See also times of other orders of magnitude.