The cellphone is the world’s most ubiquitous computer. The four billion cellphones in use around the globe carry personal information, provide access to the Web and are being used more and more to navigate the real world. And as cellphones change how we live, computer scientists say, they are also changing how we think about information.

It has been 25 years since the desktop, with its files and folders, was introduced as a way to think about what went on inside a personal computer. The World Wide Web brought other ways of imagining the flow of data. With the dominance of the cellphone, a new metaphor is emerging for how we organize, find and use information. New in one sense, that is. It is also as ancient as humanity itself. That metaphor is the map.

“The map underlies man’s ability to perceive,” said Richard Saul Wurman, a graphic designer who was a pioneer in the use of maps as a generalized way to search for information of all kinds before the emergence of the online world.

As this metaphor takes over, it will change the way we behave, the way we think and the way we find our way around new neighborhoods. As researchers and businesses learn how to use all the information about a user’s location that phones can provide, new privacy issues will emerge. You may use your phone to find friends and restaurants, but somebody else may be using your phone to find you and find out about you.