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 standard keyboard layout). The Dvorak pattern was designed with the belief that it would significantly increase typing speeds with respect to the QWERTY layout. Dvorak believed that there were many problems with the original QWERTY keyboard pattern such as: Dvorak studied letter frequencies and the physiology of the hand and created a new pattern to alleviate the above problems, based on the following principles: The Dvorak pattern is intended for the English language. For other European languages, letter frequencies, letter sequences, and bigrams differ from those of English. Also, many languages have letters that do not occur in English. For