From root: Why no mathematical symbols?
What do the colours mean?
The blog has a consistent visual scheme of 3 main colours in addition to plain white.
The blue colour is used to define data objects.
Magenta is used for labelling and providing additional context, but it can also serve as a standard ‘alternate’ to black.
Black is the baseline choice for defining the diagram structure.
References and further reading
Crameri, Fabio, Grace E. Shephard, and Philip J. Heron. 2020. “The Misuse of Colour in Science Communication.” Nature Communications 11: 5444. https://doi.org/10.1038/s41467-020-19160-7.
Hardwick, Robert J. 2026. “What is the visual grammar of these diagrams?” umbralcalculations, September. https://umbralcalc.github.io/posts/what_is_the_visual_grammar_of_these_diagrams.html.
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