Tablets and smartphones really are personal computers, only smaller. Touch input is changing the way we use PCs, but Windows 7's keyboard-and-mouse UI is essentially unchanged from Windows 95, which debuted 17 years ago. Windows 8's touch-oriented Metro interface will require Windows users to relearn some fundamental tasks. (Like, where did the Start button go?) But the touchy UI is a logical evolution of Windows, one that allows the OS to expand not just to consumer tablets, but also to industrial and enterprise applications where touchscreens are more practical than keyboards and mice.