Take a line segment. Nothing very exciting so far. Divide it into three and remove the middle section to construct an equilateral triangle, as shown in the figure below.
That already looks a little prettier. What if we repeated the process on each of the resulting segments?
The figure produced by repeating this simple transformation indefinitely is perhaps the best-known example of a fractal image: every part is identical to the whole. Starting with an equilateral triangle gives the Koch snowflake.
