Fractal theory describes objects that have self-similar patterns across different scales. Fractals are defined as geometric shapes that can be split into parts, each of which is a reduced-size copy of the whole. They often have non-integer dimensions and fine structures at arbitrarily small scales. Common examples include natural shapes like coastlines as well as mathematical constructs like the Cantor set and Koch curve. Fractals are created by recursive processes that repeat a simple pattern on decreasingly smaller scales. Their dimension can be calculated from how their size changes with scaling factor.