This book explores the fabrication of soft material and biomimetic MEMS sensors, presents a review of MEMS/NEMS energy harvesters and self-powered sensors, and focuses on the recent efforts in developing flexible and wearable piezoelectric nanogenerators. It also includes a critical analysis of various energy harvesting principles, such as electromagnetic, piezoelectric, electrostatic, triboelectric, and magnetostrictive. This multidisciplinary book is appropriate for students and professionals in the fields of material science, mechanical engineering, electrical engineering, and bioengineering.