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
Keyboard layout 1969. Consonants occupy the left side of the layout, while vowels are on the right. Sebeolsik 390 (세벌식 390; 3-set 390) was released in 1990. It is based on Dr. Kong Byung Woo's earlier work. This layout is notable for its compatibility with the QWERTY layout; almost all QWERTY symbols that are not alphanumeric are available in Hangul mode. Numbers are placed in three rows. Syllable-initial consonants are on the right (shown green in the picture), and syllable-final consonants and consonant clusters are on the left (shown red). Some consonant clusters are not printed on the keyboard; the user has