Abstract
Nanotechnology based on nanomaterials has made breakthroughs in almost every field in daily life, including electronics, food and agriculture industry, environment, and healthcare. This chapter focuses on the fundamental and applications of nanoparticles in healthcare, with a special emphasize on recent advances of nanoparticle technologies and their applications in diagnostics and therapies. In order to better understand the development of nanomedicine, we will first introduce the concept of nano, the definition and historical development of nanotechnology.