High-Frequency Trading (HFT) is one of the most controversial topics in the markets today. This type of trading involves the use of computer algorithms to rapidly open and exit positions in stocks at the speed of light. The benefit to many HFT firms is that they can execute trades and react faster to price changes in the market before any their competitors.
Here is a historical time-line of the impact of high-frequency trading (HFT) in the financial markets.