Definition

Tests where users (as opposed to proxy-users or user representatives) evaluate the usability of a product or service, searching for defects.

Comment

Most so-called user tests don't engage users to do the testing. When performing the most effective user tests, all the different profiles of users must participate and they must be managed to ensure that they perform tests that represent all the work that they will complete using the product or service under test.

Also see: UAT, User Testing