Volume 3 looks at classes of biomolecules including carbohydrates, nucleic acids, and lipids. In addition, special areas of application are included, such as pharmaceuticals, natural products, isotope ratio methods for biomolecules analysis, and clinical applications. The articles are arranged under general headings for continuity and ease of access, although several of these are of interest across the various disciplines. The articles are intended to teach and therefore strive to cover basics and sufficient additional detail to bring the reader up-to-date on a given subject. Some advanced topics are also covered, either in a special section of articles or in additional reading citations.