Fiber-based materials have shown their important role in almost all fields of science, including energy harvesting, optics, communication, water purification, and electrocatalysis. Their abundance, flexibility, structural reformation, high surface area, tunable chemical composition, and abundant composite forms make the fiber one of the most desirable materials for current and future devices. Earlier, considerable research efforts have been carried out with natural fibers, especially in the field of textiles; however, once synthetic fibers came into the picture, they changed the scenario. Synthetic fibers are nowadays highly used in wearable devices. The network of synthetic fibers facilitates charge transportation, and their large surface makes them vibrant candidates for electrochemical application. Our daily life has utilized several types of fiber materials for a long time. In the early days, natural fibers, including loops of jute, coir, and bamboo, were utilized for several applications. However, nowadays, synthetic fibers and their composites with natural fibers play a major role in making human life easy. The advanced fiber-shaped materials can be used in various applications including electronics, sensors, catalysis, and photonics. The present chapter deals with the basics of natural and advanced fibers and their few applications. Finally, the research challenges have been discussed and the prospects of fiber materials have been proposed.