What is a butterfly put spread and how can it be used in options trading strategies?

A butterfly put spread is an options trading strategy that involves buying one put option at a lower strike price, selling two put options at a middle strike price, and buying one put option at a higher strike price. This strategy can be used to profit from a specific range of price movement in the underlying asset, with the maximum profit occurring if the asset's price stays close to the middle strike price at expiration.