The book describes the properties, characteristics and optical response of fiber Bragg gratings(FBG, reviews the fabrication techniques of FBG, Fabrication of FBG by Phase Mask method, Relation of FBG reflectivity and laser parameters, and Mechanical strength of FBG. It also elaborates the development and construction of FBG sensor and highlights the concerns explored before and during the installation of FBG sensor. The various experimental setups for data collection based on strain and temp measurements are also explained. The results of fabricated FBG are analyzed together with theoretical calculations and the results of manufactured FBG in terms of wavelength-strain/temp sensitivity, dynamic range; linearity and sensitivity of FBG sensor system and defined the relationship between sensor gauge length and wavelength shift, axial strain, and sensitivity of FBG system. This book illustrates the performance evaluation of FBG sensor for strain measurements in comparison with the existing/ traditional methods. Conclusion drawn from the finding and the recommendations for further work are presented. It highlights the contribution of study to the body-of- knowledge.