# Availability | | In reliability engineering, the term **Availability** has the following meanings:The degree to which a system, subsystem or equipment is in a specified operable and committable state at the start of a mission, when the mission is called for at an unknown, i.e. a random, time. The probability that an item will operate satisfactorily at a given point in time when used under stated conditions in an ideal support environment. | |-|-| | | wikipedia:: [Availability](https://en.wikipedia.org/wiki/Availability) |