Basically i am on an A-level research product and i have chosen to study string theory. I have explained particle spin, theory of super gravity (to explain where string theories came from) and the basics of string theory. I also explained supersymmetry earlier on. My questoin is, how does supersymmetry relate to string theories to produce superstring theories? I assume it's something to do with the bosons/ fermions being symetrical again? Help please!!