1# UML state machines23UML 2.5.1 specifies states, transitions, triggers, guards, effects, pseudostates, composite states, regions, and state-machine ownership. Use those concepts when lifecycle behavior must be reviewed precisely.45Reference: [OMG UML 2.5.1](https://www.omg.org/spec/UML/2.5.1).67The renderers are presentation tools; they do not guarantee semantic validation of a UML state machine. Consider a future parser and model-checking integration.