What are Diodes?
A diode is a very simple device that provides the foundation of some of the most utilized technology in existence. A diode is essentially a device that allows electrical current to pass in one direction but not in the other. This is described as an asymmetric transfer characteristic. Diode can be made out of semiconductors, vacuum tubes and other components.
In a diode, the direction in which current can flow is described as the forward direction. The direction in which current is completely blocked is called the reverse direction. This complete resistance to flow in a specific direction allows diodes to be used for what is called rectification, the changing of AC current into DC current.
The description above describes the simplest type of diode. Other types of diode have more sophisticated functions. For example, there are some diodes available