Dvorak Simplified Keyboard closed out. Apple also includes a Dvorak variant they call "Dvorak – Qwerty ⌘". With this layout, the keyboard temporarily becomes QWERTY when the Command (⌘/Apple) key is held down. By keeping familiar keyboard shortcuts like "close" or "copy" on the same keys as ordinary QWERTY, this lets some people use their well-practiced muscle memory and may make the transition easier. Mac OS and subsequently Mac OS X allow additional "on-the-fly" switching between layouts: a menu-bar icon (by default, a national flag that matches the current language, a 'DV' represents Dvorak and a 'DQ' represents Dvorak – Qwerty ⌘) brings
Keyboard layout keys (this however includes more processing from the keyboard hardware, and can therefore be slightly slower, with a lag that may be noticed in daily use). A few companies offer "ABC" (alphabetical) layout keyboards. Some keyboard layouts for non-Latin alphabetic scripts, most notably the Greek layout, are based on the QWERTY layout, in that glyphs are assigned as far as possible to keys that bear similar-sounding or appearing glyphs in QWERTY. This saves learning time for those familiar with QWERTY, and eases entry of Latin characters (with QWERTY) as well for Greek users. This is not a general rule, and