How much oil is there left on Earth? Can science replace the fossil fuels we use? The 'Why Science Matters' series demonstrates how the science we learn at school is important in every aspect of our everyday lives. Using case studies and investigations, the series describes the development of science and technologies that can improve our lives – or lead to new scientific challenges and controversies. In 'Finding and Using Oil', we find out science and technology help us find, refine and use the chemical also known as “black gold”. We learn the importance of understanding the chemistry of hydrocarbons, how they can be separated into useful fuels, and how oil is the basis for plastics. And there’s discussion of the world’s oil reserves, their sustainability, and our continued reliance on oil as a fuel.