On Branes and Oriented B-fields

Novel theories appear on the world-volume of branes by orienting B fields along various directions of the branes. We review some of the earlier developments and explore many new examples of these theories. In particular, among other things, we study the pinning effect of branes near conifold like singularities and brane-antibrane theories with different fluxes on their world-volumes. We show that all these theories arise from different limits of an M-theory configuration with appropriately chosen G-fluxes. This gives us a way to study them from a unified framework in M-theory.