ABSTRACT
The familiar shapes of two-dimensional geometry are shown in the first sections of this
chapter. Scale is entirely relative for these figures. Later sections show how triangles,
squares, and hexagons can be combined into more complicated shapes; these can serve
as building blocks for even larger patterns, and some are capable of tiling the plane. The
final section treats closed curves that are not strictly polygons because they have arc-like
edges rather than straight-line edges.
