By popular request, I put together a "Back to Basics" video on diodes. The video doesn't go into the semiconductor physics or any heavy math, it just gives some good practical information about how to think about typical diode behavior (IV characteristics) - from "ideal" behavior, working towards more "real" behavior. It also briefly discusses some of the many different types of diodes. Demonstrations are shown. Links to many of the previous videos I've done on more specific diode types and applications are also included in the YouTube video description notes.
Enjoy: