Difference between link: and link[]

Google search link:URL and link[URL] return different results

[birwin]

I am curious to know the difference between the link:URL and link[URL] searches at Google.

I have a very new site and the link:URL search is returning no results whereas the link[URL] search returns about 20 results.

[ciml]

For the second search, you're seeing pages that mention the word "link" and the URL.

[Just Guessing]

I wouldn't like to hazard a guess as to what the first search would show you.;)