RPGMemes

Easy enough that I had to read your comment a few times to read it with the non-aggro tone you intended lol

The hard part is when there's a community built around a game system with its own traditions and rituals. That's never in the books. This is only an issue with bigger systems like V:tM, Pathfinder, and Shadowrun, but you just need to learn to play them from other people just like you learned to play D&D.