A section is a cut through the 3d-model. An elevation is different. It shows the face of something, or perhaps more correct, the projection of an object/s to a plane.
Project Definition: Establishing Scope, Vision and Work Effort. In order to have any realistic shot at a successful project, (delivered on time and on budget) the overall vision and work effort must first be fully defined --- i.e. broken down into small, manageable and actionable parts.
For :Wikipedia:WikiProject, see Project (disambiguation). In contemporary business and science, a project is an individual or collaborative enterprise, possibly involving research or design, that is carefully planned, usually by the project assigned team, to achieve a particular aim.