This document provides an overview of biodiesel, including its history, definition, applications, advantages, disadvantages, and future potential. It discusses biodiesel being made from vegetable oils or animal fats through a process called trans-esterification. Applications include use in vehicles, generators, and marine vessels. Advantages include being renewable and less polluting, while disadvantages include higher costs. The future of biodiesel is seen to lie in genetically engineered microalgae which can potentially be used to completely replace petroleum-derived diesel fuels. The document also presents a case study on Iran and how microalgae cultivation could help meet its future biofuel needs.