Recommended
Grounding - Safety Fundamentals (1hr:13min:19sec)
Why people recommend it
A lengthy but widely cited explanation of why mains grounding works and how it clears faults, recommended for anyone confused about earth connections.
Watch for: Long runtime, focused on mains wiring rather than low-voltage circuits
In their words
I initially got the idea after watching the famous Mike Holt video on grounding.
Jtl on electronics.stackexchange.com, Nov 2018. CC BY-SA.