Google introduced a feature to its mapping service on Wednesday that allows people to create their own customised maps, by adding information such as the location of cheap petrol stations or property for sale.
The information comes from what Google calls maplets, which are small applications created by Google or a third-party developer that combine Google Maps with some other service, such as a real estate listing or traffic report.
Users who set up a Google My Maps account can then create their own customised maps, adding as many maplets as they want. They can also draw directions on their maps, and attach photographs or videos of specific locations using services such as Google's YouTube and PicasaWeb.
The resulting maps can be kept private or made public and indexed in Google's search engine, according to Google's My Maps page. People can also upload maps to Google Earth in the form of a Keyhole Markup Language (KML) file, a technology for describing geographic coordinates.
A Google official said last month that the company may eventually allow paid advertisements on its mapping service, where businesses would be able to create maps with some sponsored links. The ads would take the form of the pins seen on the maps today, with pop-up photos and text.
It would be a way for both Google and businesses to earn more advertising revenue, which underpins much of Google's strength. Google has said it will give users some say in how many ads appear on its maps, so as to not be too intrusive.