Some useful video tutorials

Diodes, how do they work?
Transformers, How do they work?
Transistor, how do they work?
How do MosFets work?
How does a Potentiometer work?
DC-motor, how do they work?
Ohm’s law explained
Binary counting and computing

Old School explanation of Free electrons
How does electricity work?
How logic gates work
How does an Antenna work?