These are the sketch notes.

Digital ones were created on Samsung Galaxy 8, using Autodesk Sketch Express (and Autodesk Sketchbook) Exported using Airdroid, and did minor post-processing on OSX (preview app)

Later, I have drawn several using good old pen-and-paper (and were scanned)

I am grateful to Sacha Chua for the inspiration.

Thanks Sunni Brown for the Visual Notetaking 101 course.

Click on the following sketch, to see others