There are three fundamental use cases for color in data visualizations:
we can use color to distinguish groups of data from each other, to represent data values, and to highlight. The types of colors we use and the way in which we use them
are quite different for these three cases.
Color as a Tool to Distinguish
We frequently use color as a means to distinguish discrete items or
groups that do not have an intrinsic order, such as different countries
on a map or different manufacturers of a certain product. In this case,
we use a qualitative color scale. Such a scale contains a finite set
of specific colors that are chosen to look clearly distinct from each
other while also being equivalent to each other. The second condition
requires that no one color should stand out relative to the others. Also,
the colors should not create the impression of an order, as would be the
case with a sequence of colors that get successively lighter. Such
colors would create an apparent order among the items being colored,
which by definition have no order.
Many appropriate qualitative color scales are readily available. Figure 4-1 shows three representative examples. In
particular, the ColorBrewer project provides a nice selection of
qualitative color scales, including both fairly light and fairly dark
colors [Brewer 2017].
Figure 4-1. Example qualitative color scales. The ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month, and much more.
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.
Julian F.
Head of Cybersecurity
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.
Addison B.
Field Engineer
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.
Amir M.
Data Platform Tech Lead
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.
