The expression "Do not fold, spindle, or mutilate" first appeared in the 1960's, and applied to what?

This now-famous warning was a critical instruction printed on the fragile paper rectangles that powered the dawn of the digital age. In the 1960s, before keyboards and screens became standard, room-sized mainframe computers were programmed using stacks of punched cards. Each card, often produced by IBM, held a single line of code or a piece of data, represented by a pattern of small, precisely located holes. These stacks of cards were a physical embodiment of a computer program.

The stern command, "Do not fold, spindle, or mutilate," was a literal and crucial directive. The cards were fed into a mechanical reader that detected light passing through the holes. A simple fold could jam the complex, high-speed machinery. Puncturing a card on a spindle, a common way to file paper receipts at the time, would create a new hole that the computer would misread as data, corrupting the entire program. Any tear or mutilation could render a card unreadable, potentially halting a massive computation and forcing programmers to painstakingly search for the single flawed card among thousands.

Beyond its practical origins, the phrase quickly became a cultural touchstone. It came to symbolize the impersonal and rigid nature of the new computerized bureaucracy, where individuals could feel reduced to a mere data point. The expression was famously co-opted by student activists during the Free Speech Movement at UC Berkeley, who wore signs with the slogan to protest being treated like anonymous, machine-readable objects by the university system.