  This review is devoted to strings and branes. Firstly, perturbative string
theory is introduced. The appearance of various types of branes is discussed.
These include orbifold fixed planes, D-branes and orientifold planes. The
connection to BPS vacua of supergravity is presented afterwards. As
applications, we outline the role of branes in string dualities, field theory
dualities, the AdS/CFT correspondence and scenarios where the string scale is
at a TeV. Some issues of warped compactifications are also addressed. These
comprise corrections to gravitational interactions as well as the cosmological
constant problem.
