Final answer:
Validation rules are Boolean expressions that ensure data integrity by verifying data against predefined criteria before allowing a record to be saved.
Step-by-step explanation:
The Boolean formulas that validate record data when a user tries to save the information are known as validation rules. These rules check the entered data against certain criteria and conditions before allowing the record to be saved. If the data does not meet the criteria, the system will prevent the record from being saved and usually provides an error message explaining why the validation failed. This ensures data integrity and conformity to business processes within the system. Whereas workflow and assignment rules are used to automate processes and actions based on certain triggers, validation rules specifically deal with validating data input.