Since the 1960s, laser and optic fiber advances have become a big success story for optical fiber networking and advanced infrastructure. The medium and manner in which people communicate have drastically improved across the world and the quality of communication for people has greatly increased. The first chapter provides an outline of the ideal waveguide for optical fiber, its capacity to provide knowledge, the degree of imperfection, and the proliferated waveguide leading to the transmission of ray theory. The following chapters describe modes and signal variations of optical fiber cabling simple optical fiber and fiber electrical light sources. Such topics are accompanied by a description of the characteristics and implementation of photodiodes, the development of a photo-detection physical model, circuit models for various detector types, and a predictive or noise model for an optical receiver performance forecast. The chapters, in conclusion, explain the theory and practice for designing receivers and transmitters and also the architecture elements of multi-terminal networks. Another big use of optical fiber, optical fiber sensors have also been rapidly evolving and received a great deal of interest both in basic science research and in practical applications. Sensing is also associated with individual sensory organs in the information system.