# pico (p)

Pico (p) is the prefix for a trillionth. In decimal notation it is a zero with 12 digits behind the decimal point: 0.000.000.001, in exponential notation it is: `10^-12`.

The prefix pico is defined like all other mathematical prefixes in the SystÃ¨me International( SI) and is used for the size indication of capacities, but also for time-related indications.