This document provides an overview of pharmaceutical compounding and related topics. It discusses drugs and their sources, classifications, uses and dose forms. Key points include: drugs can come from natural, synthetic or semisynthetic sources; they are classified as over-the-counter, prescription, or controlled substances; and have therapeutic, diagnostic or preventative uses. Solid dose forms include tablets, capsules and other types; liquid forms include solutions and suspensions; and delivery systems can control drug release rates. The document aims to define important terms and compare different drug properties and formulations.