The Relative Strength Index (RSI), developed by J. Welles Wilder, is a momentum oscillator that measures the speed and change of price movements. The RSI oscillates between zero and 100. Traditionally the RSI is considered overbought when above 70 and oversold when below 30.
Some of the successful RSI trading strategies are:
RSI + MACD
RSI + MA Cross
RSI + RVI
RSI + Price Action