Biodiesel is a renewable and biodegradable form of diesel derived from vegetable oils, animal fats, or recycled grease. Biodiesel offers a number of benefits compared to standard diesel, including environmental and safety benefits. This book includes five chapters that explain various aspects of biodiesel. Chapter One focuses on various aspects of biodiesel production from microalgal species that have the potential to remediate different types of wastewaters. Chapter Two aims to show whether microreactors can replace conventional biodiesel production processes and how this replacement technology could be carried out. Chapter Three studies the effects of Cynara biodiesel-bioethanol-diesel fuel mixtures on engine performance characteristics. Chapter Four presents a study of flash point and refractive index in biodiesel/butanol and biodiesel/diesel/butonal blends. Lastly, Chapter Five presents how microbial biodegradation may ultimately affect the overall degradation of hydrocarbons, including biodiesel.