Data Analysis: Frequency Polygons vs Boxes to compare histograms of different datasets

Histograms are created using boxes representing bins, and no doubt they seem to have been aptly selected for depicting the quantity populated into a bin. However, the histogram becomes cluttered if we want to compare two or more datasets.

A better way to represent bin's height would be to place a polygon at the specified height(frequency of the bin), one for each dataset. Hence, bin values of different datasets would render being visually distinct.