Wanted to post it, before noticing that @klk had already posted it a few days back. Unfortunately, it didn't get much love, which is a pity, as 3Blue1Brown rarely disappoints explaining complicated topics in an intuitive way. So here it is again.

Some of the quantum stuff here is part of my daytime job, but I must admit I also answered the initial pop quiz question in his video incorrectly. At any level of knowledge, I think you'll get something from this video.