Short interest refers to the total number of shares of a particular stock that have been sold short but have not yet been covered or closed out. It’s a key indicator used by traders and investors to gauge market sentiment, particularly with respect to bearish sentiment (i.e., the expectation that the stock price will decline).

Key Concepts:

• Short Selling: This is a strategy where investors borrow shares of a stock and sell them with the expectation that the price will drop. They plan to buy the shares back later at a lower price, return them to the lender, and pocket the difference as profit.
• Short Interest: The number of shares that are currently sold short but have not yet been bought back. It's typically expressed as an absolute number or as a percentage of the stock's total outstanding shares.

Why Short Interest Matters:

1. Market Sentiment: High short interest can indicate that a large number of investors are betting that the stock's price will fall. Conversely, low short interest suggests that investors are more optimistic or neutral about the stock.
2. Short Squeeze Potential: When short interest is high, there’s a risk of a short squeeze—a situation where the stock price unexpectedly rises, forcing short sellers to buy back shares to limit their losses, driving the price up even further. This can lead to sharp price increases in a short period.