It is the equivalent of placing a citation in a published article. This will return pages in the AltaVista database which include links to this site. This valuable resource allows you to see what kinds of sites have linked to the site in quesiton. A careful look at the author and content of a site is essential before considering if the information is reliable. Consider the reputation and credentials of the author and publisher of the site.
Corroboration is an important test of truth.
It is a good idea to find at least three sources that agree. If the sources do not agree, do further research to find out the range of opinion or disagreement before you draw your conclusions. Anyone can publish on the Web. The author or source of information should show some evidence of being knowledgeable, reliable, and truthful. The name of the author may be at the top or bottom of the Web page.