Due to tremendous increase in bandwidth capability brings a convergence of voice, video and data over a single fiber-optic channel. An alloptical network will be part of a complex combination of networks including wireless and wireline technologies developed throughout the world. The number and complexity of fiber optic devices and systems has increased dramatically, and the skills and knowledge required to work on these systems has expanded as well. The book will be useful for engineering students to understand the basic concepts of optical fiber, opto electronics and optical fiber communication without the use of rigorous mathematical explanation. It will also serve for those students who are preparing for various competitive examinations and appearing for interview in various telecom companies. In addition to that the book will also cater for professionals involved with fiber optics, service engineers and technicians.