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The History of the "Undo" Function?

Posted by Cliff on from the better-than-a-eras^H^H^H^Hbackspace-key dept.

TheLocustNMI asks: "So, earlier today as I was typing out some magnum opus of a stored procedure, I highlighted to copy it, and hit SPACE instead of Ctrl-C. Without thinking, I hit Ctrl-Z to 'undo' my folly. Pausing a moment to reflect, I realized that I own countless hours of thanks to whomever came up with the "undo" button. In short -- my question is this -- where did it come from? What are the earliest implementations of the 'undo'? (a quick googling returns this page, a cornucopia of undo and history related treatises)"

4 of 61 comments (clear)

  1. Try thinking "Command-Z" ... by tdelaney · · Score: 5, Informative

    That's right people ... Apple did it first (at least in a consumer machine).

    The original Macintosh had "undo" functionality in its applications, right from the start.

    The Apple IIGS also had "undo" functionality.

    There may have been one or two individual applications before it (I don't know) but the Mac made "undo" ubiquitous.

    1. Re:Try thinking "Command-Z" ... by tdelaney · · Score: 4, Informative

      Although, IIRC there wasn't originally a command key associated with it ... you had to go to the menu.

      "Command-Z" was chosen to match with the existing command keys of "Command-V" (paste), "Command-C" (copy) and "Command-X" (cut). All the major editing command keys were in the one location.

  2. Re:alt.folklore.computers by crisco · · Score: 5, Informative

    Best advice here. A search of google groups yields one thread that points to Undo existing in the late sixties.

    --

    Bleh!

  3. ancient history of undo/redo by js7a · · Score: 5, Informative
    was there a documented implementation of Undo on a computer before the original Mac?

    Yes, MIT's Lincoln Reckoner had multiple-level undo/redo in 1968. That used a screen editor, so it would be the kind of undo you are talking about, however it was probably inspired by IBM's APL line-based workspace editor.

    APL programmers had multiple-level undo/redo on their selectric typewriters around 1965. Each interaction was numbered, and you could select the number of the last interaction you wanted to keep. This would reset the entire workspace so that all variables, your program image, and options would be restored. This worked by saving the workspace each time a command completed, and was also useful for restoring sessions after interrupted connections.

    Single-level undo appeared much earlier -- the first IBM teletype line editors in the late 1950s had single-level undo.