This page is testing how search engine indexing robots traverse relative links: links that refer to pages on the same site by their location in relation to the linking page. For more information, see the Relative Links Test page, and the Robot Indexing Test page.
This page is only linked to by the Relative Links Test using problematic syntax <../../../../../test/relativelink/test5.html>. A robot which attempts to follow this link will go beyond the root directory of the web server, which is not allowed. Most robots will simply fail to index this page, but a few will start from the root and locate it. You can test this by searching for the code below.
Search Codes: RTest, RTest175, RTestGood, RTestGood175