Tell them it's a massively multiplayer online game where people try to out do each other with the cleverest posts in order to win hit points called "karma". Even though the players are from all over the world everyone assumes your character is a white, American male even if you tell them otherwise.

There are clear rules to the /r/reddit game posted on every "sub reddit" but there are a lot of unwritten rules as well. For example professing a love of popcorn in an inappropriate space will diminish your hit point to a level you will never recover and the correct answer in /r/relationships is always "hit Jim and delete Facebook".

Currently the level I have the highest score on is /r/askreddit, but there is no way to predict why that is because one of my most popular posts is about me giving empathy to a man who was served shrimp for the first time and he didn't know how to eat it because the restaurants left the shells on.

If someone really likes a post you wrote then they will pay actual money and award you with "gold" which will allow you to temporarily access exclusive features of the game. If someone likes your post but has no real money theyay choose to award you /r/reddit silver, which for some reason I always find hilarious good times..