Google has a pretty good idea of where you are when you search the Internet, and henceforth it will respond to your search queries by including a map accompanied by relevant local results.

Previously, Google provided local search results when explicitly asked to do so, as in a query like "coffee in San Francisco." Starting Monday, the inclusion of local search results in Google search results listings becomes default behavior, whether or not a location is included in a query.

"We like to make search as easy as we can, so we've just finished the worldwide rollout of local search results on a map, which will now appear even when you don't type in a location," said Google software engineers Jenn Taylor and Jim Muller in a blog post. "When you search on Google, we will guess where you are and show results near you."

Google and other Web services are able to identify users' whereabouts are through IP address geolocation, which tends to be accurate unless a proxy is being used to conceal location data.

Users of mobile devices can be located via cell tower triangulation or GPS data, if their phones include a GPS module.

Google previously assumed that local search results were desired in any search from a mobile device and delivered them by default. It continues to rank local search results requested through mobile devices more prominently than results for the same search conducted through a desktop computer.

For example, a search for "coffee," made through Google, the Safari mobile browser, and an iPhone, returns a link to Wikipedia's "coffee" entry first, followed by a list of three local results, and then a link to Starbucks.

The same search made through Google, Firefox, and Windows XP returns three search results -- Wikipedia, Starbucks, and CoffeeGeek -- and three Google News search results, before any local search listings.

Google's search app on the iPhone provides still different behavior. When the query "coffee" is entered but before it's executed, it includes "search for 'coffee' near me" as the first auto-complete search refinement suggestion in a list of several other suggestions.

Google offers users the option to change their location using the "Change location" link at the top right side of the block of local search results, a feature that's particularly useful for travelers planning to visit a certain city or region.

Google has long seen local search as a promising revenue opportunity because businesses will pay a premium to advertise to those who, through their searches, express interest in a product or service and who happen to be nearby.

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