The purpose of this School is to provide an introductory set of lectures on string theory for beginners in the field. The School will begin with a discussion of the quantization of strings, their low energy effective theories and their compactifications, and will lead up to recent developments in the non-perturbative aspects of string theory such as D-branes, string dualities and dualities between string theories and gauge theories (e.g. AdS/CFT correspondence). TOPICS INCLUDE: - BOSONIC & FERMIONIC STRINGS, HETEROTIC STRING - SUPERGRAVITY ACTIONS AND THEIR CLASSICAL SOLUTIONS - TOROIDAL & CALABI-YAU COMPACTIFICATIONS - D-BRANES & OPEN STRINGS - STRING DUALITIES - STRING THEORY/GAUGE THEORY DUALITY