Control-C else, typically returning control to the user. Ctrl-C was one of a handful of keyboard sequences chosen by the program designers at Xerox PARC to control text editing, with Ctrl-Z (Undo), Ctrl-X (Cut), Ctrl-V (Paste), and Ctrl-P (Print). The first four letters are all located together at the left end of the bottom row of the standard QWERTY keyboard, and P towards the upper right. The equivalent key combination on Macintosh computers is Command-C. Control-C as an abort command was popularized by TOPS-20 and TOPS-10 and adopted by other systems including Unix. It was also adopted by Digital Equipment operating
Dvorak Simplified Keyboard will travel 25 kilometers (16 mi) on a QWERTY keyboard and only 1.6 kilometers (1 mi) on a Dvorak keyboard. Because the Dvorak layout requires less finger motion from the typist compared to QWERTY, some users with repetitive strain injuries have reported that switching from QWERTY to Dvorak alleviated or even eliminated their repetitive strain injuries; however, no scientific study has been conducted verifying this. The typing loads between hands differs for each of the keyboard layouts. On QWERTY keyboards, 56% of the typing strokes are done by the left hand. As the right hand is dominant for the majority