String theory has gone through many name changes over the years. This list provides an at-a-glance look at some of the major names for different types of string theory. Some versions have more specific variations, which are shown as subentries. (These different variants are related in complex ways and sometimes overlap, so this breakdown into subentries is based on the order in which the theories developed.) Now if you hear these names, you’ll know they’re talking about string theory!
Bosonic string theory
Superstring theory (or Supersymmetric string theory)
Type I, Type IIA, Type IIB, Heterotic string theories (Type HE, Type HO)
M-theory
Matrix theory
Brane world scenarios
Randall-Sundrum models (or RS1 and RS2)
F-theory