In economics and finance, arbitrage (/ ˈ ɑːr b ɪ t r ɑː ʒ /, UK also /-t r ɪ dʒ /) is the practice of taking advantage of a price difference between two or more markets: striking a combination of matching deals that capitalize upon the imbalance, the profit being the difference between the market prices at which the unit is traded. Index arbitrage An investment trading strategy that exploits divergences between actual and theoretical futures prices. An example is the simultaneous buying (selling) of stock index futures (i.e., S&P 500) while selling (buying) the underlying stocks of that index, capturing as profit the temporarily inflated basis between these two baskets. Often, the Short-term demand that is not perfectly elastic can lead to temporary price pressures and create room for arbitrage opportunities. If this is the case, index funds will buy stocks entering the