Back in the 1940s, WWII engineers used the binary system to label individual power buttons, toggles and rotary switches: a 1 meant “on,” and a 0 meant off. In 1973, the International Electrotechnical Commission vaguely codified a broken circle with a line inside it as “standby power state,” and sticks to that story even now. The Institute of Electrical and Electronics Engineers, however, decided that was too vague, and altered the definition to simply mean power.
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I read somewhere that a broken circle with a line meant the power switch physically disconnected the power, while a complete circle with a line inside meant “standby” where the power remained physically connected in the device.
I read somewhere that a broken circle with a line meant the power switch physically disconnected the power, while a complete circle with a line inside meant “standby” where the power remained physically connected in the device.