Last week I had possibility to participate in pProgramming Blockchain seminar (programmingblockchain.com) by Jimmy Song. One of his students made great video explanation of how bitcoin protocol works.
It's a little hardcore and may be complicated to understand for people without software engineering background but still it's best such short and visual explanation of how bitcoin works I ever seen. If you're looking to code any kind of bitcoin related application (e.g. accepting bitcoins in e-shop), starting from this video may be great shortcut.