https://www.reuters.com/article/us-retail-trading-gamestop-explainer/explainer-how-retail-traders-squeezed-wall-street-for-bets-against-gamestop-idUSKBN29W2NC

A surge of retail stock trading over the last year lit the fuse that sent shares of GameStop Corp rocketing higher without a clear business reason, market watchers say, squeezing hedge funds that had bet against the video game retailer and other companies that were out of favor on Wall Street.