If you enter text into the Location bar that is not a valid Internet address (URL), Firefox will try to direct you to the location you intended.

Internet Keyword search

Firefox will first try to send your request to a keyword search service. By default, this service is Google's Browse by Name service. For example, If you type mozilla foundation into the Location bar, Firefox will submit a query to the Google Browse by Name service, since this is not a valid URL. The service will find its best match for your request, and direct you to http://www.mozilla.org. An entry without a clear match to a URL will display search results for the entry.

Turning off and on

You can control whether the Internet Keywords search is active by editing your Firefox configuration.

1. Type about:config in the address bar and press EnterReturn.
   A warning page may appear. Click Accept the Risk and Continue to go to the about:config page.
2. Search for the preference keyword.enabled.
3. Double-click the keyword.enabled preference to toggle it between true and false.

• • false disables Internet Keyword searches.
  • true enables Internet Keyword searches.

Changing the keyword service

You can specify any valid URL to perform the Internet Keyword searches by modifying the keyword.URL preference in the about:config page:

• To use the Browse by Name service from in earlier versions of Firefox, keyword.URL can be set to http://www.google.com/search?ie=UTF-8&sourceid=navclient&gfns=1&q=. Google will forward you to the relevant site if it finds a clear match. Otherwise, the search results page will be displayed.To set the the Internet Keywords service to perform a Yahoo! search, keyword.URL can be set to http://search.yahoo.com/search?p=. The text you entered into the Location Bar will be appended to the url.
• To use Bing, set keyword.URL to http://www.bing.com/search?q=.
• To reset the Internet Keywords service to use a standard Google search, right-clickhold down the Ctrl key while you click on keyword.URL and select Reset.

Domain Guessing

If you enter an incomplete URL, Firefox can try to "fix up" the URL by adding a prefix, suffix, or both to what you types. For example, if you type www.mozilla the Location Bar, Firefox will append .com to complete the URL. If you type mozilla.org, Firefox will prepend www. to complete the URL. This "guessing" is secondary to the Internet Keywords search described above - it does not work unless Internet Keywords are disabled.

Turning off and on

You can control whether Domain Guessing is active by editing your Firefox configuration.

1. Type about:config in the address bar and press EnterReturn.
   A warning page may appear. Click Accept the Risk and Continue to go to the about:config page.
2. Type fixup into the Filter prompt at the top of the about:config page.
3. Double-click the browser.fixup.alternate.enabled preference to toggle it toggle it between true and false.

• • false disables Domain Guessing.
  • true enables Domain Guessing.

Changing the prefix or suffix

You can specify a prefix (such as www) or suffix (such as .net) for the Domain Guessing feature.

In the about:config page, double-click the browser.fixup.alternate.prefix or browser.fixup.alternate.suffix preference. Enter in the prefix or suffix you want Firefox to add to incomplete URLs.

Based on information from Location Bar search (mozillaZine KB), Domain Guessing (Mozilla.org End user documentation), and Internet Keywords (Mozilla.org End user documentation)