What does the symbol on a power button mean? How did it come about?

In the 1950s, the universal power symbol we see on modern devices was created to represent the binary concept of on and off, using a circle and vertical line to symbolize 1 and 0. Originally used for standby mode as well, the power icon remains a recognizable symbol for toggling devices on and off. This symbol’s history and significance shed light on the design choices made for everyday icons we encounter.

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