The AppleDesign Keyboard replaced the Apple Extended Keyboard II in 1994 and its design was meant to complement the design of Macintosh computers of the time. This keyboard included one additional ADB port (instead of two) that was somewhat hidden on the bottom of the keyboard. The ADB connector cable was permanently attached to the keyboard, while previous keyboard models used two ADB ports and shipped with an ADB cable that could be removed.
This keyboard was also released in black to match a black Performa 5420 (available in Europe), and a black Power Macintosh 5500 (available in Asia).
As of 2020 Apple has released approximately 20 external keyboard designs. In general, Apple Macintosh keyboards are different from standard keyboards because they include a Command key (⌘) for shortcuts; an Option key (⌥) for entering diacritical marks and special characters; and a Help or fn (function) key. Earlier Apple keyboards also included a power key (◁), while newer keyboards include eject (⏏).
Source: Wikipedia