Chapter 1: Supercomputers and application performance.- Chapter 2: Performance optimization of applications.- Chapter 3: Case studies of performance optimization of applications.- Chapter 4: O(N) methods.- Chapter 5: Acceleration of Classical Molecular Dynamics Simulations.- Chapter 6: Large scale quantum chemical calculation.About the Author: Masaaki Geshi is an Associate Professor at the Institute for NanoScience Design at Osaka University. He received a Ph.D. in science from Kanazawa University in 2000. His research interests include materials design, from first-principles calculations to the synthesis process for new materials, and high-pressure physics.