The book is illustrated with roughly 1000 original figures. Most were drawn by the author in Adobe Illustrator. A few were drawn in Photoshop. All are available here in PNG format.
Most of these images are saved at high resolution (300 dpi or better), so they are appropriate for presentations and talks even when projected to large size.
All of these figures are released under the MIT license, like the code. This means you're free to use them any way you like, as long as you keep the copyright associated with them somehow. Use them for your classes, reports, papers, presentations, whatever you like!
You're not required to attribute me or the book if you use these images, but I'd appreciate it if you would.
Some figures include photographs. Many of these are by the author. All other photos are from Wikiart, Wikimedia, or Pixabay. The book provides a citation and URL to the source of each of these images. The first two sites state that their images are in the public domain. All images selected from Pixabay are labeled as released under the Creative Commons CC0 license, and explicitly state, "Free for commercial use. No attribution required."
To help you better sort through and choose figures, thumbnails for all the figures are available.
The figures for Volumes 1 and 2 are each in their own GitHub repo:
Any other resources will be available in their own repository.