[quietbritishjim]

No, the one-inside-a-circle symbol does not indicate a toggle between off and on, as this article "surmises".

Instead, it indicates stands by. This is off, but not fully off as a circle would suggest. It's nearly on. The symbol is great for that.

On a push button it means activate stand by or come back out of it (i.e., turn back on fully). Still fair enough.

Unfortunately, this knowledge has watered down over time. I've seen that symbol used more than once for a button that only turns on a device (never back to stand by). That's pretty much the opposite of its original meaning.

[CharlesW]

> No, the one-inside-a-circle symbol does not indicate a toggle between off and on, as this article "surmises".

According to https://en.wikipedia.org/wiki/Power_symbol#Standards, "one inside a circle", IEC 60417-5010, is a fully-on/fully-off toggle. The "one breaking a circle" symbol, IEC 60417-5009, is a fully-on/standby toggle.

[quietbritishjim]

Agreed but the "one breaking a circle" stand by symbol, IEC 60417-5009, is what the article seemed to be referring to by "one inside a circle", given the pictures shown. I just copied their imprecise description.

[gorlilla]

I'm glad you clarified. The symbol has always represented an open 'O' vs closed '|' circuit to me (never bothering to look at the standards). The fully inside vs breaking is still fitting in that context.

[CharlesW]

Ah, I see now, thank you.

[saalweachter]

This makes ⏻ even more appropriate as a fashionable T-shirt design, since I too only toggle between an on and sleep state, and never* fully power off.

[rezonant]

Eventually we all become the O.

[saalweachter]

Yeah, but we hardly ever toggle back on.

[mrexroad]

Interesting! Per your Wikipedia link… there was an early ‘00s proposal for a dedicated sleep symbol: line through a crescent moon. Same proposal would have defined line-through-circle as the generic power symbol. Though, this was superseded with standard for using only a crescent moon to indicate standby.

“Standby symbol ambiguity

Because the exact meaning of the standby symbol on a given device may be unclear until the control is tried, it has been proposed that a separate sleep symbol, a crescent moon, instead be used to indicate a low power state. Proponents include the California Energy Commission and the Institute of Electrical and Electronics Engineers. Under this proposal, the older standby symbol would be redefined as a generic "power" indication, in cases where the difference between it and the other power symbols would not present a safety concern. This alternative symbolism was published as IEEE standard 1621 on December 8, 2004.”

Edit: formatting, verbosity.

[contingencies]

there was an early ‘00s proposal for a dedicated sleep symbol: line through a crescent moon

This may have been avoided owing to strong potential of religious misinterpretation.

[troymc]

I don't think I've ever seen the ⏼ symbol, only ⏻, but maybe I'm weird.

[JohnFen]

Interesting. I remember when that symbol was first getting used, but I don't remember anyone ever explaining that until you just did now. To me, it always meant "on/off" (counting "standby" as "off"). I thought it was just an artistic way of taking the "1" and "0" that was often used on power toggle switches and combining them into a single symbol for a single pushbutton (the "1" is inside the stylized "0").

[FrankSansC]

Exactly, there's even standards[0] for this.

[0] https://en.wikipedia.org/wiki/Power_symbol#Standards

[eviks]

Indeed, and even in 2008 when this article was written Wikipedia had this explanation

> IEC 5009, the standby symbol (line partially within a broken circle), indicates a sleep mode or low power state. The switch does not fully disconnect the device from its power supply.

https://en.wikipedia.org/w/index.php?title=Power_symbol&oldi...

[nytesky]

I think it’s mostly true for modern usage. Powering off a laptop doesn’t fully disconnect power, because the power button is not a true switch but just signals to some power management hardware which is ALWAYS on as long as there is battery charge or plug power — it catches the signal from the “power” button and executes a true power switches to start the computer boot cycle.