Validation rules, allow you to validate the data that is entered by the end-user. With this rule, you can notify the users if some conditions are not valid and the user is trying to take an action.
Validation Group Name
Name of the validation group that attached to action. You can leave empty to execute validation always.
Error Message
The error message that will be shown to the user when rule is validated.
Rule Condition
The condition for the validation. If this condition is valid, the error message will be shown and form will not be validated.