String/M-theory and its progress

We report the significance of string/M-theory and the two revolutions in the course of its development as well as its major achievements, review its current status and trends, and discuss how the study of this theory can deepen our understanding of a quantum gravity theory and reveal the conditions which a consistent unified theory including gravity must meet. Current progress of this theory has revealed, to certain extent, the nature of space-time and its fuzziness, the nature of interactions and their fuzziness, and the possible fuzziness between classical and quantum descriptions when non-perturbative effects are taken into consideration. These may guide the further progress and lead to the completion of this theory.