What is the difference between Test Case and Tested By link types in TFS

Question

If I open a User Story in VS and go to the All Links Tab I can add a new lint where the Work Item Type is test Case and I have a choice of Link Types.

However, if I go to the Test Cases tab, I can add a link to a Test Case but only with the Link Type of Tested By.

Can anyone explain to a relative TFS newbie what the difference is when adding a link on each of the 2 tabs and perhaps what the various Link Types are supposed to represent?

Answer 1

Found this article on StackOverflow. Guess I should have tried there first. https://stackoverflow.com/questions/2627629/work-item-link-types-in-visual-studio-tfs-2010