That yellow first-down line shown on televised football games isn’t really on the field. But to viewers, it appears to be there, just like the turf and the players. The technology, developed by Sportvision and called 1st and Ten, is an early commercial example of a field of computer science called augmented reality, in which the real world is overlaid with virtual information. Once the stuff of science fiction, augmented reality is now also making its way to smartphones, thanks to advances in both hardware and software.
People in Amsterdam who download a free application called Layar on their cellphones can look through the camera and see information about nearby restaurants, A.T.M.’s, and available jobs displayed in front of buildings that house them. This information is provided by companies like Hyves, the Dutch social networking site, and ING, the financial services company. The businesses pay a fee to SPRXmobile, the privately held company based in Amsterdam that developed Layar.
http://www.nytimes.com/2009/07/12/business/12proto.html?_r=1
http://www.youtube.com/watch?v=b64_16K2e08
