What is RSI? How can you trade with RSI?

The relative strength index (RSI) is a technical indicator. Basically it is used in charts to understand if the particular stock has the strength in terms of volumes to reach a price point. A high RSI indicates higher volumes. RSI is measured in a scale from 0 to 100. RSI above 70 indicates a healthy volume and below 30 indicates a low volume. It is often seen that traders BUY when RSI is above 70 and SELL when RSI is below 30. It is a lagging indicator, thereby make sure you couple with other indicators to get correct signal.