Do you know the difference between an AT-AT and an AT-ST? Do you know at least five phrases in Klingon? Can you play "snake" on YouTube? If not, you'd better get cracking if you want to maintain your geek cred. You don't want to get caught without these essential skills at the next Comic-con. Here are fifty things every geek should know, thanks to a handy infographic by Virtualhosting.com.