Algorithmic trading is a process for executing orders utilizing automated and pre-programmed trading instructions to account for variables such as price, timing and volume. An algorithm is a set of directions for solving a problem.Eighty percent of the daily moves in U.S. stocks are machine-led.Banks regularly use algorithmic trading strategies and have high-frequency trading firms as clients.In the twenty-first century, algorithmic trading has been gaining traction with both retail and institutional traders. It is widely used by investment banks, pension funds, mutual funds, hedge funds and even retail traders.