PhD Lecture 4: Black hole microstates and exotic branes: We will discuss supergravity representations of black hole microstates and the possible role played by exotic branes.

PhD Lecture 3: Exotic branes: We will see that duality predicts various low-codimension objects called exotic branes, and discuss their peculiar properties.

PhD Lecture 2: Supergravity solutions: We will discuss the supergravity solutions representing various brane configurations and see how the duality transformations are manifested in them.

PhD Lecture 1: String theory and branes: We will review the extended objects in string theory and the duality transformations relating them