  In this lecture note, I discuss why many of us are expecting rich physics at
the TeV scale, drawing analogies from the history of physics in the last
century. Then I review some of the possible candidates of new physics at this
energy scale. I also discuss why we believe much of the matter in the universe
is not atoms (baryons) or compact astronomical objects, and hence requires
physics beyond the standard model. Finally I discuss some of the candidates for
the non-baryonic dark matter.
