In Forex trading, correlation is a statistical technique that measures the relationship between two assets.The coefficient is measured in decimal form from -1 to +1.
A position correlation of two pairs shows that two currency pairs will move in the same direction. A negative correlation of two pairs indicates that two currency pairs will move in the opposite direction.
An example is the correlation between EUR/USD and GBP/USD. If EUR/USD is trading up, then GBP/USD will also move up, in the same direction.