This book highlights the main advances in fiber electronics, like fiber-shaped solar cells, batteries, supercapacitors, sensors, light-emitting devices, memristors and communication devices from the standpoints of material synthesis, structure design and property enhancement. It focuses on revealing the separation and transport mechanisms of charges, establishing transport equations for electrons and ions, and emphasizing integration methods in fiber devices. In closing, it reviews emerging applications based on fiber devices that could accelerate their large-scale production in the near future. Given its scope, the book offers a valuable resource for scientists, engineers, graduate students and undergraduate students in a wide variety of fields such as advanced materials, energy, electrochemistry, applied physics, nanoscience and nanotechnology, polymer science and engineering and biomedical science. It also benefits many non-specialist industrialists who are working to promote new technologies.