there's a new project by the creator of the fantastically successful series of periodic videos - short youtube films for each element on the periodic table (explosive sodium was my favorite!).
the new project is called sixty symbols and shows scientists at the university of nottingham describing the squiggles and letters that physicists and astronomers regularly use to communicate with each other! if you want to read the youtuber comments, you can also watch the videos at the youtube channel.
there are lots of good videos so far, but my favorites might be the one about mass:
and the one about big numbers: