Image zoom Credit: Getty Images. Art:Jillian Sellers. Earlier this week, struggling U.S.-based video game retailer GameStop made headlines when its stock jumped (and jumped again) after day traders that frequent WallStreetBets, a subreddit, an online community on the social platform Reddit, coordinated to get stock prices up. We're talking a huge jump: From $17.25 per share at the start of the year to $159.18 on Monday. This caused a lot of chaos on Wall Street. While most people know the stock market exists, not everyone knows how it actually works, especially when terms like "hedge funds," "short sellers," and "options" enter the equation.