The Cult of the Dead Cow (cDc) has released Goolag: a google scanner for searching website vulnerabilities and other juicy information using Google. The scanner is based on google hacking techniques developed by Johnny Long. The tool comes with its own dork database and helps in scanning fast.
As defined by JohnnyLong in his hacking database: googledorks are Inept or foolish people as revealed by Google.
Technically, dorks are search patterns that reveal sites with potential vulnerabilities. Check the hacking database for the extensive list of dorks. These search patterns are not specific to google but just that its more effective with google because of its vast index.
An example dork from the hacking database is "intitle:admin intitle:login" which gives Admin Login pages. Now, the existance of this page does not necessarily mean a server is vulnerable, but it sure is handy to let Google do the discovering for you, no? Let's face it, if you're trying to hack into a web server, this is one of the more obvious places to poke.