annotation
Personal annotations
Yehudi Menuhin, a great violinist, marked up a score for Bach's Sonata No. 2 for Solo Violin. Penciled annotations show real-time performance strategies. To outsiders, insider markups appear chaotic and cryptic, but these personal annotations are for Menuhin's eyes, the only eyes that matter. All can learn from this useful workaday grid strategy: a relevant and intense data layer can become a coherent substrate scaffold upon which to overlay additional information. Maps do this all day long.
Trees and graphs
A tree is a kind of graph, but a graph can be considerably more complex than a tree.
I have reason to believe, which for brevity’s sake I will treat elsewhere, that the most complex class of processes and structures we humans can consciously prescribe, reduces mathematically to a tree. A tree has a top, bottom, left and right. Its branches fan out from the trunk and they don’t intersect with one another. They are discrete, contiguous, identifiable objects which persist across time. Trees are Things.
Software and websites, however, reduce to arbitrarily more complex structures: they are graphs. A graph has no meaningful orientation whatsoever. No sequence, no obvious start or end—at least none that we can intuit. It is better considered not as one Thing, but as a federation of Things, like the brain or a fungus network, or perhaps a composite artifact left behind from an ongoing process, like an ant colony or human city.