Algae, lipids, feedstocks, phototrophic, heterotrophic, biofuel, bioenergy. Algae can be converted into biofuel through photosynthesis or fermentation. With improvements in technology, algae could meet global demand for liquid fuels and help address issues of population growth, urban sprawl, infrastructure, and energy/oil prices. However, large-scale algae cultivation faces challenges of land and water use and potential environmental impacts that require further research into more sustainable methods.