A Bearish options strategy that involves short selling or "writing" call options. When the stock falls below the strike price of the call options by expiration, the call options expire worthless and the entire premium from sale is earned.
When you short sell, you are actually selling a security without owning it, hoping that you can buy it later when the price falls and repay your loan. ghu
For example, today you are sure that company X stock price will go down in the next two weeks and it's priced today to be 10 $, you sell it today at 10$ without owning it (you are actually borrowing it from your your broker). In 2 weeks, your broker will ask you what you have borrowed. When the price is 5$ on that day in the market, you will buy it and give it to the broker. Your profit will be 5$ minus all the cost related to the transaction.