Stop button on Full Graphics Smart Controller freeze the system

Hi.
I'm just starting out with building my first 3d printer. While waiting for some parts to come in I started playing with the LCD.
The lcd is hooked up to a ramps1.4 board and arduino. Marlin is used for the firmware and the lcd works great.
One thing that I have seen is that when I press the stop button on the lcd board it freezes the system. I don't know if it freezes the arduino or only the lcd board.
Does anyone have any experience with this ?

Isn't that what it is supposed to do...immediately stop all processing/movements, power down the heaters, and wait for you to push the reset button?????

So in other words it is a PANIC button and not a simple STOP-PAUSE/RESUME button.

It's called a "kill" button and its function is defined in Marlin to stop everything. It's an alternative to the power switch which is sometimes hard to reach, or "pulling the plug" which takes more time and is sometimes under the table, etc...

You will need to check Marlin and see how it is configured. I have seen the button on a genuine RRD GLCD used as a "back" button in the LCD menus on other firmware, and some of the RRD clones have two buttons each configured to do different things.....