LSC Language Reference
An LSC specification is a finite set of live sequence charts.
Step and Superstep
Every execution of an event is considered a step. Sometimes, multiple events that are defined to be simultaneous are executed in a single step. In execution context, some events are driven by the user, while others are triggered by the system. Following a user action, the PlayGo can optionally execute a super step – a sequence of steps which terminates when the next event must be a user action, or when the entire execution is terminated.