info Google Operator

The info operator shows a site's summary and provides links to the cache, related, link, and site search, if available. Just like the cache operator, this operator requires a valid URL for it to work.

Example: info:www.google.com

As mentioned earlier, this operator is basically the cache, related, link, and site operators rolled into one and is useful as an all-in-one replacement for these operators.

link Google Operator

The link operator searches for HTML links to a particular page.

Example: link:ntu.edu.sg

Note that Google shows the number of hits as usual, followed by "linking to ntu.edu.sg". This indicates a correct link search.

Take care that the link submitted should be a valid URL. An invalid URL will cause the link operator to become an ordinary search term.

This operator should not be used with other operators or search terms; doing so will convert the link operator into a search term.

Compare the link operator with the site operator. The site operator shows no result for an invalid URL whereas the link operator shows results of different context depending on the validity of the URL submitted.

You can use sub-domains to narrow search results. A neat trick is to use this operator to search for backlinks to a particular page of your site. Note that the results may not be the same as those shown in Google Analytics or Google Webmaster Tools.

site Google Operator

One of the more useful operators, the site operator is used to restrict a search to a particular URL or domain name. It is commonly used to search within a known website.

Example: site:americanexpress.com travel

Note that Google matches the domain names from right to left instead of the usual left to right. Therefore, all URLs used with the site operator must end with a valid registered top-level domain name.

Include sub-domains to narrow the search results.

Examples:

site:home.americanexpress.com travel

site:home.americanexpress.com/home travel

Compare the difference in the number of hits between all the above examples.