Apple Wireless Keyboard the initial release. The new model now uses only two AA batteries instead of three originally. Additionally, Mac OS X 10.5.8 is now the minimum OS over the original Mac OS X 10.4.10. This model of keyboard became standard with new generation of iMacs introduced on the same day. On July 20, 2011, following the release of Mac OS X 10.7/OS X Lion, Apple updated the keyboard slightly, updating the label on the Exposé key to Mission Control and changing the Dashboard key to a Launchpad key. Keyboard layouts with a rectangular Enter key are available in American English and
QWERTY Edison's 1872 electric print-wheel device which later became the basis for Teletype machines; Lucien Stephen Crandall's typewriter (the second to come onto the American market) whose type was arranged on a cylindrical sleeve; the Hammond typewriter of 1887 which used a semi-circular "type-shuttle" of hardened rubber (later light metal); and the Blickensderfer typewriter of 1893 which used a type wheel. The early Blickensderfer's "Ideal" keyboard was also non-QWERTY, instead having the sequence "DHIATENSOR" in the home row, these 10 letters being capable of composing 70% of the words in the English language. Alternating hands while typing is a desirable trait