The Companies That Defined 2021 By: TalkMarkets December 31, 2021 at 05:12 AM EST Robinhood’s eventful year reached its peak when the stock trading app was caught in a frenzy involving retail traders, short sellers, and “meme stonks”. Read More >> Related Stocks: Coinbase Global, Inc. Facebook Netflix Pfizer Robinhood Markets Inc Cl A Tesla, Inc.