[sofayam]

I know a suprising number of people 10-20 years older than me who regularly use desktop computers but do not understand what a window is e.g.: that windows can cover each other up, and that there are special places you must grab or click them to either resize or move them, that you can shrink them into a dock without closing the application etc.

Rather ironic considering that the operating system they all use is actually named after this, for them, inscrutable abstraction.

Those guys at Apple knew what they were on to when they created iOS with its one app at a time paradigm, even if it is slowly adding all that complexity back in to the more recent versions.