This course is an introduction to branes in string theory and their world volume dynamics. Instead of looking at the theory from the point of view of the world-sheet observer, we will approach the problem from the point of view of an observer which lives on a brane. Instead of writing down conformal field theory on the world-sheet and studying the properties of these theories, we will look at various branes in string theory and ask how the physics on their world-volume looks like.