Old school D3 from simpler times

A simple and effective form for visualizing magnitude is this gridded layout of colored squares. Each individual square represents one unit; each small row represents ten units; the small rows are grouped into ten, representing one hundred; lastly, ten groups per large row represents one thousand. This arrangement affords quick and natural reading of exact counts by powers of ten.

For an example of this technique in practice, see Randall Munroeâ€™s Radiation Dose Chart.

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