What defines a "link?"

Trying to make sense of the links in madness

[conecticslib]

I was wondering if there was a definition of a "link in" for Googfle or other search engines.

When I search my site on search engines, I find many more links than Google records...including key foreign sites that don't come up. (Key for me, since my topic is related to culture from another country.) My indirect competitors link to me - those don't show in Google's links in, nor do links from many other pages.

Does anyone know exactly how "links in" are determined?

[Marketing Guy]

Are you refering to the "backlinks" feature on the Google toolbar or in their search?

If so, it only shows links on pages that are PR4 or above.

Google (presumeably) does know your links are their, but they just don't display them.

Scott