A worldwide energy crisis and increased greenhouse gas emissions are driving the search for renewable energy sources. The use of microalgae biofuels is expected to replace fossil fuels as a major source of renewable energy for sustainable development. A wide range of micro- and macroalgae have been explored as potential biofuel feedstocks. Most algal biomass also contains polysaccharides (sugars), pigments, minerals, antioxidants, and lipids (triglycerides), which are the raw materials for the production of bioethanol and biodiesel. Oil crops and lignocellulose-based biofuels suffer from major drawbacks, but microalgae biofuel has none. Algae-based biofuels have a number of advantages: a) Algae grow fast, b) High biofuel yields can be achieved with algae, c) Algae do not compete with agriculture, d) The microalgal biomass can be used as a fuel, feed, and food source, e) Algae can purify wastewater, f) Algal biomass can be used as an energy source, g) Algae can be used to produce many useful products, h) The algae industry is a job-creation engine including being technically and economically viable, cost-competitive, consuming minimal water, and emitting the least amount of CO_2, . The algae are considered a clean renewable energy source, as they do not pollute the environment.