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 typists could be retrained to Dvorak in a mere 10 days, though he discarded at least two previous studies which were conducted and whose results are unknown. With such great apparent gains, interest in the Dvorak keyboard layout increased by the early 1950s. Numerous businesses and government organizations began to consider retraining their typists on Dvorak keyboards. In this environment, the General Services Administration commissioned Earle Strong to determine whether the switch from QWERTY to Dvorak should be made. After retraining a selection of typists from QWERTY to Dvorak, once the Dvorak group had regained their previous typing speed (which