The MacBook Pro (sometimes abbreviated MBP)[1] is a line of Macintosh portable computers introduced in January 2006 by Apple Inc., now in its third generation. Replacing the PowerBook G4, the MacBook Pro was the second model to be announced in the Apple–Intel transition, after the iMac. It is the high-end model of the MacBook family and is currently produced with 13- and 15-inch screens. A 17-inch version was available for sale in April 2006.