Courant Algebroids. A Short History
  The search for a geometric interpretation of the constrained brackets of Dirac led to the definition of the Courant bracket. The search for the right notion of a "double" for Lie bialgebroids led to the definition of Courant algebroids. We recount the emergence of these concepts. 
Yvette Kosmann-Schwarzbach
math.HO math.DG math.SG