The PowerBook (known as Macintosh PowerBook before 1997) is a family of Macintosh laptop computers designed, manufactured and sold by Apple Computer from 1991 to 2006. During its lifetime, the PowerBook went through several major revisions and redesigns, often being the first to incorporate features that would later become standard in competing laptops. The PowerBook line was targeted at the professional market. In 1999, the line was supplemented by the home and education-focused iBook family. The PowerBook was replaced by the MacBook Pro in 2006 as part of the Mac transition to Intel processors. 680x0-based models PowerBook 100 series In October 1991, Apple released the first three PowerBooks: the low-end PowerBook 100, the more powerful PowerBook 140, and the high end PowerBook 170, the only one with an active matrix display. These machines caused a stir in the industry with their compact dark grey cases, built-in trackball, and the innovative positioning of the keyboard that left room for palmrests on either side of the pointing device. Portable PC computers at the time were still oriented toward DOS, and tended to have the keyboard forward towards the user, with empty space behind it that was often used for function key reference cards. In the early days of Microsoft Windows, many notebooks came with a clip on trackball that fit on the edge of the keyboard molding. As usage of DOS gave way to the graphical user interface, the PowerBook's arrangement became the standard layout all future notebook computers would follow. The PowerBook 140 and 170 were the original PowerBook designs, while the PowerBook 100 was the result of Apple having sent the schematics of the Mac Portable to Sony, who miniaturized the components. Hence the PowerBook 100's design does not match those of the rest of the series, as it was actually designed after the 140 and 170 and further benefited from improvements learned during their development. The PowerBook 100, however, did not sell well until Apple dropped the price substantially. The 100 series PowerBooks were intended to tie into the rest of the Apple desktop products utilizing the corporate Snow White design language incorporated into all product designs since 1986. Unlike the Macintosh Portable, however, which was essentially a battery-powered desktop in weight and size, the light colors and decorative recessed lines did not seem appropriate for the scaled-down designs. In addition to adopting the darker grey colour scheme that