Book excerpt: This extensive and comprehensive handbook systematically reviews the basic physics, theory and recent advances in superconductivity. Covering the entire field, this unparalleled resource carefully blends theoretical studies with experimental results to provide an indispensable foundation for further research. Leading researchers, including Nobel laureates, describe the state of the art in conventional and unconventional superconductors. In addition to full-coverage of novel materials and underlying mechanisms, the handbook reflects continued, intense research into electron-phone based superconductivity.