Slot with small circle that moves left or right - which is on and which is off?
 

Using the Firefox web browser I often see the above. For example on the options page of Adblock Plus, and elsewhere on the internet. The intention is to allow the user to turn some option on or off.

But nothing tells you if left is off and right is on, or if left is on and right is off.

Which one is it, and is it the same 100% of the time throughout the internet-universe?

And why do web designers assume that everyone will know which is which? It would have been courteous to see something that says "on" or "off" according to the position of the circle.

Note that the national conventions for physical switches vary from country to country: https://en.wikipedia.org/wiki/Light_switch#Orientation

Thanks.

Usually, right and colored means ON and left and greyed out means OFF.

99 times out of 100, these things are as you would expect; dual-position. And they're coded to work like that.

Whatever mode it's in when you click it, doing so will cause it to flip to its 'option'. A second click will return it again. You CAN carefully 'drag' the thing by clicking on the wee circle and holding while you move it, but it's simpler just to click.....and click again to return.

As shruggy says, usually a colour change of some kind is involved, though not always. All depends how the developer of the "widget" has coded it to work.....though convention dictates that left is normally "Off" & right is normally "On".


Mike. :hattip:

Well, I never tried them out in an RTL environment (like Hebrew or Arabic). Perhaps the orientation changes there as well. Or maybe not.

Adding to the confusion, different themes will render switches differently.

Check boxes did not have this ambiguity.
Ed

Thanks.

So left is off, and right is on. Usually.

I do not recall ever seeing a colour change.

It is a difficult and apparently unsolved design problem to create symbols that unambiguously mean on and off. Even the broken line open switch symbol of electronic circuit diagrams could be mistaken for being on, as a gate that opens to let something flow out. Although perhaps as EdGr wrote, a tick/check versus an X is the closest.

On/off is (was?) usually done with radio buttons, which only allow one “on” a set..on/off would be a set of two…
Checkboxes are designed to allow multiple selections. That said, if the design had only one checkbox for a value, it could be tested for checked or not checked.
I suspect if one looked under the covers of the css used to display the “switch” graphic being discussed, we’d find a single checkbox.
I have seen that used where it was not as intuitive as it could have been, but that was mostly because the the text said something like “If you want to turn this feature off, turn the switch on.”…but not as clearly.

It's a question of your theme's highlight color.
Color highlighted == On.

You might be using the wrong theme then.

No, it isn't.

The computer industry is famous for not being able to agree on how many buttons to put on a mouse. ;)
Ed

This has no bearing on or relation to my statement.
But I'm happy for you for the opportunity to share this random trope from the world of technology.
;)

My best idea for universal on/off symbols would be a circle with say six or eight short lines sticking out around the circumference to represent on, in other words a very simple cartoon of the sun, and the same size circle made of a dotted line and without any rays to represent off.

Another idea could be an open eye for on, and a closed eye for off.

I've no idea how the symbol on my washing machine switch, and also seen on ublock on my brower etc, is ever meant to represent on or off. It is baffling and completely uninformative.

It came from 1 being on and 0 being off, as frequently used on rocker switches, and hopefully that part shouldn't be confusing.

When push buttons started being used for power, that convention doesn't work - a combined symbol was needed.

Originally a line breaking the circle was "standby" and the line inside an unbroken circle was "power on-off", but since power often doesn't go completely off these days, someone decided to introduce a crescent moon (for "sleep"), and use the standby symbol as the standard one, with power on-off being reserved when zero power needs to be a guaranteed state.

There's a 1.4MB 126 PDF on the subject if you're really interested.