| element of a function chart participating in the definition of the state of the system at a given instant where this element may be either active or inactive|
Note 1 to entry: Steps are separated by transitions.
Note 2 to entry: The set of active steps defines the state of the system considered.
Note 3 to entry: Commands or actions may be associated to each step. A step can only activate a command if it is active.
Note 4 to entry: This entry was numbered 351-29-23 in IEC 60050-351:2006.