OverLay Chart - two pairs on one price chart
OverLay Chart - information display for MetaTrader 4 terminal. Many traders, using multicurrency trading strategies, wish to visually observe the price movement of selected pairs on one price chart to compare some parameters of their movement. OverLay Chart indicator is just the right way to help in this matter.
In the example shown, the USDJPY chart is superimposed on the EURUSD.
Commentary from ForTrader.org: Actual to use OverLay Chart indicator when determining the correlation of currency pairs or their volatility. It is very convenient to use it if you trade cross pairs using the major ones. And in other variants.