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 international standard ISO/IEC 9995-2, although this is not explicitly required by the US American national standard. US keyboards are used not only in the United States, but also in many other English-speaking places, including India, Australia, English Canada, Hong Kong, New Zealand, South Africa, Malaysia, Singapore and Philippines. However, the United Kingdom and Ireland use a slightly different layout because of the Irish language. The US keyboard layout has a second Alt key instead of the AltGr key and does not use any dead keys; this makes it inefficient for all but a handful of languages. On the other hand,