The put-call ratio is a popular metric used by traders and investors to gauge market sentiment and potential price movements. It is calculated by dividing the number of put options traded by the number of call options traded over a specific period. A high put-call ratio indicates that more traders are buying puts, which can signal a bearish market sentiment, while a low ratio suggests a preference for calls, indicating bullish sentiment. The put-call ratio is often used as a contrarian indicator; for instance, extreme levels of either a high or low ratio may suggest that the market is overbought or oversold, potentially signaling a reversal. Investors use this ratio to make informed decisions about the likelihood of a market correction or continuation of the prevailing trend. As with any indicator, it is most effective when used in conjunction with other technical and fundamental analysis tools.