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
QWERTY the Remington No. 2 of 1878, the first typewriter to include both upper and lower case letters, using a shift key. The QWERTY layout depicted in Sholes's 1878 patent is slightly different from the modern layout, most notably in the absence of the numerals 0 and 1, with each of the remaining numerals shifted one position to the left of their modern counterparts. The letter M is located at the end of the third row to the right of the letter L rather than on the fourth row to the right of the N, the letters X and C are