Hedge fund people borrowed stock from GameStop stock owners and sold it at a price. They intended to make other stockholder sell out of panic, so that stock prices would go down. They would then buy the stock for cheap and return the borrowed stock to the stock owner at the agreed upon date, netting a fine profit. This is called short stocking. Wall Street Bets learned of this and decided to interfere. They bought the devalued stock and decided to hold on to it until Friday, January 29th. That is the date by which Hedge Fund Manages must pay their stocks back to the owners. By holding onto the stock, the price has skyrocketed, which will cause Hedge Fund Managers to lose money trying to buy stock back. That isn’t the goal though because these corporations can bounce back from that. The goal is to make them default on their agreement with the original owners of the stock, thus having to pay them enough money to be able to buy the stock plus a premium fee. Thus, massively screwing over the corporations.

Edit:

There is no time limit on this endeavor, as we have now seen. The hedge fund managers must pay the owners back but it does not have to be Friday. They have actually doubled down on their bets, granting them another week. At this rate, the debt is going to skyrocket beyond their ability to pay.