Highly correlated currencies
This report should be leaned to get most info about heading trends.
It means that Bitcoin price can be leaded by other, more mighty cryptocurrency, or maybe some market trend have affect on it.
Low correlated currencies
This report should be leaned to build highly diversified portfolio.
It makes sense to mention that a low correlation in this case includes not only coins whose movements are not statistically related but, on the contrary, move in opposite directions (in the case of a negative value of the parameter)