Are Forking and Joining in State Diagram Same as that in Activity Diagram?

Fork and join are commonly used in UML activity diagram. Although it is not too common to use fork and join in state diagram, it is allowed in UML and the semantic meaning of notation is the same as in the UML activity diagram.

Side note:
"Note - A transition may have multiple sources (in which case, it represents a join from multiple concurrent states) as well as multiple targets (in which case, it represents a fork to multiple concurrent states)."

UML User’s Guide, Chapter 21 - State Machines, Grady Booch James Rumbaugh Ivar Jacobson - Addison Wesley.

Useful UML Resources

• OMG UML Specification
• The Best UML modeling software
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