Apple recently unveiled its new wireless printing technology for iOS called AirPrint. The new technology will be made available as part of the new iOS 4.2 update that is to be released in November this year. What AirPrint does is basically detect printers in the neighborhood that are compatible with wireless networks and pass on text, image or other documents to the printer wirelessly for these files to be printed on paper.
At this point, AirPrint can interact wirelessly with the HP ePrint printers. Apart from this, you can also connect to any printer that is connected to a Mac or a PC. AirPrint is designed to work with a wide range of printers and so the device at your home or office should most definitely be included in the list of supported devices.
Check out this video walk-through of AirPrint in action. The demo was made by folks at WhenWillApple.com