Hi  

• A business rule is a server-side script that runs when a record is displayed, inserted, updated, deleted, or when a table is queried. Business rules are triggered based on server-side conditions and can automate actions in response to database operations (1, 2).
• Business rules can be configured to run at different times relative to a database operation: Before (after form submission but before database action), After (after database action), Async (scheduled job after form submission), and Display (before the form is shown to the user) (1, 2).
• They apply to record operations such as Insert (new record creation), Update (modifying a record), Query (searching for records), and Delete (removing a record) (1, 2).
• Use cases for business rules include aborting database actions and restricting access to records 3.
• For new process automation, Workflow Studio is recommended as it offers easier extension, reuse, and upgrade capabilities, but business rules remain important for existing automations (1, 2).
• Business rules do not honor Access Control Rules (ACLs) unless explicitly configured to do so (1, 2).

https://www.servicenow.com/docs/r/australia/build-workflows/business-rules-classic/c_BusinessRules.h...