Development of computer science techniques has significantly enhanced computational electromagnetic methods in recent years. The multi-core CPU computers and multiple CPU work stations are popular today for scientific research and engineering computing. How to achieve the best performance on the existing hardware platforms, however, is a major challenge. In addition to the multi-core computers and multiple CPU workstations, distributed computing has become a primary trend due to the low cost of the hardware and the high performance of network systems. In this book we introduce a general hardware acceleration technique that can significantly speed up FDTD simulations and their applications to engineering problems without requiring any additional hardware devices.