Firefox 3+ includes a useful feature called the awesome bar that helps you quickly navigate to any previously visited website without having to type the address of that page in the address bar of your browser. If you vaguely remember only a couple of words from the title of a webpage, Firefox will find it for you.
Firefox 3.5 awesome bar in action:
For example, let’s assume that you searched for "firefox location bar" on Google a few days back and want to repeat that same search today.
If you are using an older browser, you will have to type the whole search phrase in the Google box again but with Firefox 3.5, you can simply type a few characters of the query in the address bar (like "fir loc" or "loc fir" – the order of words is immaterial) and the browser will show you a list of matching web pages from your browser history that have those words (or characters) either in the title or the address (URL). Simple.
The Problem with Firefox Location Bar
Firefox’s awesome bar definitely saves time but it Mozilla recently revealed that a lot of users weren’t upgrading from Firefox 2 to Firefox 3/3.5 just because of this "awesome" location bar. The users were worried that this feature might reveal their (embarrassing) Google search queries and visits to other "dirty" websites to other people with who they share the computer.
That is the reason Mozilla added a new privacy option in Firefox 3.5 to help you turn off the smart location bar forever and keep you tracks covered.
Turn off Firefox awesome bar forever
Go to Firefox Tools -> Options -> Privacy -> Location Bar and select either "Bookmarks" or "Nothing" from the option that says "When using the location bar, suggest:". When you select Nothing, it will turn off suggestions completely from the location bar while selecting "Bookmarks" will only show matching pages from your bookmarks.