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.
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.
“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.
> 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...
The new symbols aren't any better but the UX of "push this button to turn on or off" combined with obvious lights/etc when something is on has mostly made the semantic meaning of the symbols obsolete to 99% of consumers.
https://unicodepowersymbol.com/we-did-it-how-a-comment-on-ha...
You can view most of the exhibit online: https://collection.cooperhewitt.org/exhibitions/2318807647/
Worth taking a look!
In the USA, a standard wall switch is moved "up" for on and "down" for off whereas in Europe it's the opposite. Always wondered how that came to be.
Now, let's talk about water faucets and which side is hot, and which one is cold...
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[0] - Don't know what the formal way for these are; I'm thinking of two switches hooked up in a XOR pattern to the same light - i.e. light turns on when the switches are in opposite positions, and off if they're in the same position.
These are called "three-way switches" in the US.
Having the lower position be "off" seems like a good failsafe for that sort of thing. I don't know if that's why the convention, but it is the mechanism that I use to remember what the convention is.
Stuff like coffee makers etc. It's weird.
These symbols are ubiquitous on industrial kit (and in your car, surprisingly enough), it's kind of a shame they are barely used at all else where. There's a pretty wide vocabulary of symbols.
https://duckduckgo.com/?ia=images&iax=images&q=photocopier+s...
https://static.thenounproject.com/png/4256363-200.png
Do the lines on the paper mean
"insert the side that already has writing face up, and the side that is blank face down"
OR
"these lines represent what will happen after you print but they're just being represented here for your imagination purposes even though they aren't there yet so you should really put the blank side up even though we are drawing lines on the up side"
My approach for over a decade now has been, before any "manual duplex" printing, to start by marking the top page in the tray with a little arrow pointing upwards, drawn with pencil or pen, in the bottom right corner of the page. I'd then print one page (and/or print a test page), and check the position of the arrow, to learn how the particular printer behaves.
To date, I've probably seen every possible orientation of the arrow on the output. Some printers do insane things to paper.
I've taken to just writing instructions to myself on that type of thing with a sharpie, using actual text, and/or an actual diagram. It works well with the usual beige plastic. If it's black, I usually put it on a small piece of paper and tape it somewhere it won't interfere with the operation.
Not everything has to be an icon. IMO, bad icons are far worse than no icons.
Yes. Cars used to have words like "OIL" or "TEMP" or "BRAKE" or "SEAT BELT" in the dashboad warning lights. That switched to icons, probably as a cost-savings so they could use the same parts worldwide. But at a cost in clarity.
Now that most new car dashboards have programmable LCD displays or at least a message area, better/more descriptive fault descriptions have returned.
More odd that it would be on a printer, but for a scanner, it is telling you that it will scan the side that is face up. For a printer, I'd be willing to be that icon is telling you that it is going to print on the face-up side.
https://i.imgur.com/H66aXTU.png
The "phone down hang up" button means press to get what is pictured
The "crossed out mic" button means press to get the opposite of what is pictured
That's the part that isn't clear. How do I know that the lines don't indicate "what is already printed" and the blank side indicates "the blank canvas that it wants as input"?
I wish designers might fall back on that more for ease of use instead of creating generation after generation of arcane, fleetingly extant symbols.
That's still dumb though. Why not use the universal bacon/no bacon icons?
But not he says it conveys 1 and 0... so simple... true or false. That would have been easier on my brains :)
it's funny to realize that nobody had the same interpretation of this ubiquitous thing
But here you are: cast them to booleans. 1/0 -> true/false