These are physics based buttons which allow the user to interact with pretty much anything. The use of the button do not themselves do anything but are simply activators for programmed responses which can occur either when the button is pressed, released or both. These buttons are used in the info panel which offers a good example of how they could be used.
Buttons prefab[VRTK] prefab already has this)Buttons prefab to your scene and position it Buttons/Button with your custom versionsActivation Percentage slider to set how pressed the button must be to be considered activatedButtons/StartPoint at the desired unpressed position of the buttonButtons/EndPoint at the maximum pressed position of the buttonButtons/Button is placed roughly between the start and end pointVR Button Handler script