What is a fractal? (precisely)
It's hard to be precise! Like a biologists definition of life, a single definition doesn't capture all the important qualities.
It's a new word (c. 1975) and even those who know the word may have a hard time explaining it.
Which word does fractal sound like, or look like?
Fractals provides a way to quantify the roughness of a surface and generally have:
What happens if we zoom in to the Mandelbrot set? (Courtesy Eric Schol)