High Quality Content by WIKIPEDIA articles! The Apple Adjustable Keyboard is an ergonomic and adjustable keyboard introduced by Apple Computer in 1993 for the Macintosh personal computers at a retail price of US$219. The keyboard attached to the computer via the Apple Desktop Bus (ADB). The last Apple computer released compatible with this keyboard without using a USB to ADB adapter was the Power Macintosh G3 (Blue White), as it was the last one with the Apple Desktop Bus.