What had four separate designs and replaced The PowerBook and iBook lines?
PowerBook The PowerBook (known as Macintosh PowerBook before 1997) was a line of Macintosh laptop computers that was designed, manufactured and sold by Apple Computer, Inc. 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, and received numerous awards, especially in the second half of its life, such as the 2001 Industrial Design Excellence Awards "Gold" status, and Engadget's 2005 "Laptop of the Year". In 1999, the line was supplemented by the consumer iBook range. The PowerBook and iBook lines were discontinued and replaced by the MacBook Pro and MacBook families respectively by 2006.
Apple A5 The Apple A5 is a 32-bit system-on-a-chip designed by Apple Inc. and manufactured by Samsung and is the successor to the Apple A4. The A5 commercially debuted with the release of Apple's iPad 2 tablet, and also powers the iPhone 4S, iPod Touch fifth generation, Apple TV third generation, and the iPad mini. This is consistent with how Apple debuted the A4 chip: first in the original iPad, followed by the iPhone 4, and then the iPod Touch (fourth generation). Apple claims that compared to its predecessor, the A4, the A5 CPU "can do twice the work" and the GPU has "up to nine times the graphics performance".