The debounce board has the debouncing of switch signals as a requirement, as well as providing the Raspberry Pi board with power. The theory and reason behind the debouncing of mechanical switches is that the signal provided by those switches is not clean, meaning that they don't immediately switch from open to closed. They will briefly close (make contact) before the springiness of the metal contacts causes them to open again and rapidly move between these two states, before finally settling into its final position, as we can see in the following diagram from an oscilloscope connected to a simple switch:
The result of this property ...
