Referrer

The URL of the web page from which a visitor came. The server's referrer log file will indicate this. If a visitor came directly from a search engine listing, the query used to find the page will usually be encoded in the referer URL, making it easy to see which keywords are bringing visitors. The referer information can also be accessed as document.referrer within JavaScript or via the HTTP_REFERER environment variable (accessible from scripting languages).

The source from which a website visitor came from.

a web page, containing a link to your web page, that delivered your visitor to your web page. For example, if Google's search results (for example on a search for "britney spears") contained a link to a page on your site and the user clicked on that link t