If I press the button once and release by removing my hand, will the dome remain depressed or it will bounce up automatically?
I suppose if I press the button, the Arduino will stop doing what it is doing (e.g. turn off the LED of a circuit connected to the button). Does it behave like that regardless of whether I press once and release or press and hold the button?
If I want to turn on the LED again, what shall I do? Press and release the button again?
1 - The button is momentary, it will only activate the button as long as you are holding it down.
2 - What the arduino does is entirely dependent on your code.
3 - Again, this is entirely dependent on what is in your code. You can make your code such that the LED is only on while you’re holding the button down OR you can make your code such that a press and release turns the LED on and a second press and release turns it off. OR, you can make your code such that the LED is only on while you’re holding the button down but if you hold it down longer than a few seconds the LED starts blinking. It’s pretty much whatever you want it to do!
The Big Red Button presses a small microswitch component underneath that performs the switching. There are different kinds of microswitches but these are very simple devices: a set of contacts inside are fully open or fully closed based on a mechanical input. Put another way, switches are really good at electrically connecting and disconnecting a pair of wires in response to some external action.
We might use terms like switch more often to mean something that stays toggled on or off unattended (like a desk lamp or automotive turn signal indicator, ‘Push On, Push Off or latching’) and button to describe something intended for a brief press, ‘momentary’ (like the microwave oven keys or Door Hold in an elevator, it’s usually springy) but the terms get used interchangeably a lot and either type is just touching and separating wires.
But the Big Red Button is momentary: it will toggle state when the input is applied and removed. There is a spring that collapses when you press the BRB and toggles the microswitch inside. When your pressing force is removed, the spring overcomes the weight of the button and pops back to its rest position.
The controller will have to do anything beyond that.
