String Theory : Where are we now?

Abstract

This is a brief overview on the current status of string theory for non-specialists. The purpose is to give an aspect on the nature of string theory as a unified theory of all interactions including quantum gravity and to discuss future perspectives. Particular emphases are put on the mysteries why string theory contains gravity and why it resolves the ultraviolet problems.Comment: 19 pages, 1 figure, written version of a general talk in the workshop "Frontier of Theoretical Physics", Beijing, Nov, 1999, minor typos correcte