Apple AirPrint
Apple AirPrint is a mobile printing feature that lets end users print from an iPad, iPhone (3GS or later) or iPod touch (3rd generation or later). Apps that use the iOS printing system can also use AirPrint.
AirPrint uses the Bonjour networking technologies to discover and communicate directly with AirPrint-enabled printers on the same Wi-Fi network. Additionally, iOS devices can use AirPrint to print to printers shared by a Mac OS X computer or a desktop PC.