The goal of this textbook is to significantly raise student understanding of the instruments they use regularly in the research or analytical labs. Based on the author 20+ years of teaching the book surveys the basic components common to optical spectrometers, with some emphasis on how each component works at a practical, not theoretical level. New instrumentation advances as well as links to current data and instrumentation designs are provided to allow students to become conversant with technology they will use in analytical labs. The book is split into two parts. The first part Optical Spectroscopic Components, Design, Use, Strengths, and Limitations is designed to discuss and enumerate the commonalities in design and construction of optical spectroscopic instruments. While the instruments each have a variety of components, many reappear in seemingly unrelated optical spectrometers. By developing a more global understanding of components, students can begin to appreciate design choices, and make more enlightened decisions about solving problems with optical spectroscopy in their own work. The second part Spectroscopic Methods and Applications focuses on specific types of spectroscopy and their typical applications, describing the realization of each experiment by details of relevant instrument designs utilizing the various components enumerated in Part I. The strengths and weaknesses of variations in spectrometer designs are discussed and selected modern and historical examples are given. In each section, common analytical instrumentation and experiments are discussed first, providing a groundwork and basis for comparison. Then newer more specialized methods are described and compared, or referenced, depending on their relevance to analytical application.