This book is primarily intended to be a text book for Bachelor/Master Degree students of Science, Engineering, and Technology. This book has a special role to play in the curriculum of all branches of Science, Engineering, and Technology and will hopefully present valuable guidelines to young graduates. An effort has been made to cover the fundamentals and applications of nanotechnology-sensors and devices. This book explains about the fundamentals of nanosensor devices, nano based inorganic sensor devices, NEMS and NEMS fabrication, nanoparticles for sensors and circuitry, nano-biological sensor devices, and the applications of nanomaterials in supercapacitors.