The team behind “Extra Credits” has begun a new series where they discuss mechanics and concepts behind video game design.  They are premiering their series by looking at the first level of Super Mario Bros. for the Nintendo Entertainment System.  The narrator, Daniel Floyd, and game designer, Daniel Emmons, discuss how Super Mario Bros. is able to teach players the game’s rules and mechanics without having to use a manual.  The video lasts a bit over five minutes, and they’ve scratched the surface, but this episode is definitely worth a look for those who are interested in game design, or even like learning more about Nintendo’s flagship franchise.