In mathematics, a self-similar object's exactly or approximately similar to a part of itself (for example the whole has the same shape as one or more of the parts). Many objects in the real world, such as coastlines, are statistically self-similar: parts of them show the same statistical properties at many scales. Self-similarity's a typical property of fractals. Scale invariance's an exact form of self-similarity where at any magnification there's a smaller piece of the object that's similar… (More on Self-similarity)