What are Case Assignment Rules and how do they work?

Case Assignment Rules automatically route cases to the appropriate user or queue based on criteria. Each rule consists of multiple rule entries evaluated in order — the first matching entry wins. Assignment can be triggered when a case is created or edited, and can be invoked from Web-to-Case, Email-to-Case, or when an agent manually checks "Assign using active assignment rules." Only one assignment rule can be active at a time. When no rule entry matches, the case is assigned to the default case owner defined in Support Settings.