What is a composite state in a state machine?

A composite state in a state machine is characterized by its ability to manage a nested structure, allowing for a more organized representation of states and their transitions. In essence, a composite state contains one or more substates, which can represent different conditions or phases within the broader context of that state. This hierarchical arrangement enables a state machine to exhibit more complex behaviors by grouping related states and managing transitions between them in a more efficient manner.

For example, within a composite state, you might have substates that reflect various operational modes of a system, where each substate can have its own transitions and behaviors while still being governed by the composite state's overarching rules. This design allows for clarity and modularity in state representation, making it easier to comprehend and implement complex systems with hierarchical state dynamics.