Validation and Verification (V&V) and independent but related procedures to make sure that the product, service or system/subsystem meets requirements and specifications and fulfills its intended purpose.
Verification is intended to check that a product, service, or system meets a set of design specifications.
Validation is intended to ensure a product, service, or system (or portion thereof, or set thereof) results in a product, service, or system (or portion thereof, or set thereof) that meets the operational needs of the user.