1 Introduction and Summary<div><br><div>2 Standard Model and Beyond <br></div><div><br></div><div>3 Orbifolds and Spinors</div><div><br></div><div>4 Field Theoretic Orbifolds</div><div><br></div><div>5 Quantization of Strings</div><div><br></div><div>6 Strings on Orbifolds</div><div><br></div><div>7 Structure of String Orbifold</div><div><br></div><div>8 Interactions on Orbifolds</div><div><br></div><div>9 String Orbifold Spectra</div><div>9A A gross view of Orbifold Phenomenology</div><div>9B Anomaly Cancellation</div><div><br></div><div>10 Standard-like Models from Orbifolds</div><div>10A Z3 Constructions</div><div>10B Product of prime orbifolds</div><div>10C Z12-I Constructions</div><div>10D Z6-II Constructions</div><div><br></div><div>11 GUTs from Orbifolds</div><div>11A GUTs from orbifolds</div><div>11B Flavors</div><div><br></div><div>12 Smooth Compactication</div><div>12A Calabi-Yau Compactication</div><div>12B Blowing up </div><div>12C M-theory and F-theory Ideas</div><div><br></div><div>13 Epilogue </div><div><br></div><div>Appendix A Fermionic Constructions</div><div>Appendix B Intersecting Brane Models</div><div>Appendix C Ellyptic Functions</div><div>Appendix D Useful Tables for Model Building</div><div>Appendix E Some Algebraic Elements of Lie Groups</div></div>