In South Africa we get two species of genet: the large spotted genet and the small spotted genet. The main difference between the two lies in the colour of the tip of the tail. The large spotted genet has a black tipped tail and the small spotted one has a white tipped tail. It is not really about the size. Another difference is that the small spotted genet has entirely black spots on its body while the large spotted one has black spots with a rusty coloured centre. This is Stripes the genet who regularly comes to visit me in the evenings. I’ll leave you to decide what type of genet it is? In mathematics we need to pay close attention to the notation. A slight change can mean something completely different. For example, f(x) indicates a y-value on a Cartesian plane but f ‘(x) indicates the derivative which is the gradient at any point. Small notational difference but big mathematical difference!