The BoSONIC String Theory which believes there to be 26 spacetime dimensions. The Superstring Theory which cuts the dimensions down to 10. Maxwell's Theory (M-Theory) believes spacetime to have 11 dimensions. It's the master theory at this time. It combines all of the original string theories. It is considered the Theory of Everything: MUSIC ART COLOUR SOUND plus a few more dimentions not listed here, check website.