This book is to introduce the advanced optical fiber communications and quantum communications including theory and design. There are three milestones that can be concluded: the conventional TDM transmission networks by using ten Gbps optical fiber transponder, all optical fiber DWDM communication networks, and quantum communication networks. This book is suitable for the students, teachers, and scientists in the departments of electric engineering, physics in university, and developing engineers in the IT companies. Ten Gbps optical fiber transponder (called “transponder” for short) has been successfully developed in Muliplexer Inc. in 2002 by authors. Immediately, the transponder become a new favorite to be the choice as the optical amplifier and optical data stream adder/dropper installed in USA, Canada, China, India, etc. to form a worldwide optical fiber TDM transmission network. Then optical fiber filter successfully developed gave an opportunity to setup all optical DWDM networks to form a super wide bandwidth metropolitan network, with all optical 162 channels. Each channel carries a ten Gbps optical fiber transponder. Nowadays, quantum communication network setup on the available optical fiber TDM transmission network and quantum satellite to form a worldwide quantum communication networks, which is not a dream but to be developed step-by-step in China, Australia, USA, Europe, Japan, etc. All of those will be discussed in detail in the level of theory and design.