An example of hexagonal binning using color encoding. Reload to change the random distributions.
The dot plot on the left is made (hopefully) more readable by grouping points into hexagonal cells (bins), then representing the amount of points in each cell by controlling its color (the darker, the greater the amount).
Data is normalized according to the maximum number of points in a single bin (corresponding to the largest hexagonon the map), so two different instances of this visualization cannot be compared between each other (they may use two different scales for colors).
Other types of encoding can be used to represent the size of bins (e.g. area).