tldr the Power button (she’s right, it’s a good button, but it doesn’t need a 10 minute video)

I was initially going to do a snarky TL;DW because of the click bait title, but instead the video impressed me. She first talks about the science behind microwaves and water molecules, and with that understanding she explains the benefit of microwaving certain things at 50% power. Later she gives a tip about frying stuff in the microwave. Worth the 10+ minutes!

I find Reheat is the most useful button/mode. It does the automatic on/off/on cycle for you while the food spins around. Takes longer to cook, but the food is heated more evenly.