The Test Specification is a place where a user can view and edit all of the existing Product, Component, Category, and Test case information. A user cannot look at a different versions of test cases - the database maintains the actual version only. The recommended practice is print the test specification when a testing is done.
TestLink offers organize test cases into two levels of containers: Component and Category. You can describe a content of both containers via five descriptive fields. These texts could be printed together with test cases then.