In the days when Macintoshes all came with 9″ monochrome displays, I once came upon a woman in a computer store trying to make sense of Apple’s boxy beige computer. Looking at the display, she tried to activate an on-screen button by tapping the mouse against the screen rather than sliding it around the desk to control the cursor. In doing so, she demonstrated that direct manipulation of on-screen items is often more intuitive than indirect input devices such as a keyboard and mouse.