Semiconductor diodes are of many types and are a separate topic beyond the scope of this book, hence we will proceed with the basic understanding and build upon it as we proceed. We will focus on rectifier diodes for the scope of this book.
The primary function of a rectifier diode is to act just like a check valve allowing current to flow in one direction and resisting (up to a limit) current from flowing in from the opposite direction.
In practical situations, sometimes under certain situations a reverse current is generated--such as when a motor armature is stopped, it continues to spin (due to inertia) inside the motor case until it comes to a halt.
This reverse current has the potential to flow back into other electronic components. This reverse current might lead to damage of delicate electronic parts. In order to stop this reverse current from flowing back...