Thomas Brand at Egg Freckles gives us a history lesson in Apple skeuomorphism, all the way back to the beginning:
Before the Mac there was no skeuomorphism, because there was no graphical user interface. For almost thirty years the iconography of desktop objects have greeted users as they stare into their computer screens. The desktop metaphor has given new computer users a familiar foundation to ground their experiences upon, and expert users terminology such as “files” and “folders” we still use today.
Brushed metal, DVD players, and even the calculator – Brand shows that skeuomorphism is nothing new for Apple.
Even the Newton had its share of skeuomorphism, with the lined paper metaphor greeting us in the Notes app.