The Money Flow Index (MFI) is a momentum indicator that combines price and volume to measure the buying and selling pressure of a stock. It is an oscillator that ranges from 0 to 100, with high readings indicating strong buying pressure and low readings indicating strong selling pressure. The Money Flow Index is a popular technical indicator used by traders to identify overbought and oversold levels, as well as potential reversal points in the market. It is based on the premise that the volume of a stock can be used to gauge the amount of buying or selling pressure in the market.