  The thesis begins with an introduction to M-theory (at a graduate student's
level), starting from perturbative string theory and proceeding to dualities,
D-branes and finally Matrix theory. The following chapter treats, in a
self-contained way, of general classical p-brane solutions. Black and extremal
branes are reviewed, along with their semi-classical thermodynamics. We then
focus on intersecting extremal branes, the intersection rules being derived
both with and without the explicit use of supersymmetry. The last three
chapters comprise more advanced aspects of brane physics, such as the dynamics
of open branes, the little theories on the world-volume of branes and how the
four dimensional Schwarzschild black hole can be mapped to an extremal
configuration of branes, thus allowing for a statistical interpretation of its
entropy. The original results were already reported in hep-th/9701042,
hep-th/9704190, hep-th/9710027 and hep-th/9801053.
