Substitute character actions than the last one can also be undone by pressing multiple times. was one of a handful of keyboard sequences chosen by the program designers at Xerox PARC to control text editing. Presumably these particular keystrokes were chosen because of their location on a standard QWERTY keyboard, since the Z (undo), X (cut), C (copy), and V (paste) keys are located together at the left end of the bottom row of the standard QWERTY keyboard. Substitute character A substitute character (␚) is a control character that is used in the place of a character that is recognized to be
QWERTY of letters, but the contribution was later called into question. Others suggest instead that the letter groupings evolved from telegraph operators' feedback. In November 1868 he changed the arrangement of the latter half of the alphabet, O to Z, right-to-left. In April 1870 he arrived at a four-row, upper case keyboard approaching the modern QWERTY standard, moving six vowel letters, A, E, I, O, U, and Y, to the upper row as follows: In 1873 Sholes's backer, James Densmore, successfully sold the manufacturing rights for the Sholes & Glidden Type-Writer to E. Remington and Sons. The keyboard layout was finalized