For what it's worth, Macintosh had rounded corners since its inception in 1984. They were just bitmaps in the screen corners and still addressable by software (

For what it's worth, Macintosh had rounded corners since its inception in 1984. They were just bitmaps in the screen corners and still addressable by software (and even by the mouse cursor in any context) but this demonstrates an aesthetic heritage. These software rounded corners disappeared in software when CRTs gave way to flat panels, but they are indisputably part of the Apple design aesthetic.