A Fractal is a never-ending pattern that is a special mathematical geometry with properties that reproduce a pattern over a range of scales.
Reference Definition by Fractalfoundation.org: A Fractal is a never-ending pattern. Fractals are infinitely complex patterns that are self-similar across different scales. They are created by repeating a simple process over and over in an ongoing feedback loop. Driven by recursion, fractals are images of dynamic systems: the pictures of Chaos. Geometrically, they exist in between our familiar dimensions. Fractal patterns are extremely familiar, since nature is full of fractals. For instance: trees, rivers, coastlines, mountains, clouds, seashells, hurricanes, etc. Abstract fractals, such as the Mandelbrot Set, can be generated by a computer calculating a simple equation over and over.