The complex field of civil engineering is essential to forming the constructed world that we live in. It includes the planning, building and maintenance of infrastructures such as buildings, bridges, roads, dams and water supply systems that are necessary for society. Civil engineers design and carry out projects that improve transportation, ease urban development and support environmental sustainability using the concepts of physics, mathematics and material science. They take on difficult tasks including protecting the environment, meeting the demands of an expanding population and managing natural resources.