You can create a surface that comprises a combination of points, breaklines, boundaries, and contours.
When you create a surface, the surface name is displayed in the 
Surfaces collection in the Prospector tree so that you can perform other operations, such as adding data and editing the surface.
Initially, the surface may be empty and not be visible in the drawing. Once you add data to the surface, the surface becomes visible in the drawing in accordance to the display settings specified in the referenced surface style.
Autodesk Civil 3D supports several types of surfaces:
- TIN surfaces. Formed by triangulating an arbitrary set of points.
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Grid surfaces. Formed from points that lie on a regular grid (for example, Digital Elevation Models (DEMs)). -
TIN volume surfaces. A composite surface created from a combination of points in a top (comparison) and base surface, also known as a differential surface. -
Grid volume surfaces. A differential surface based on user-specified top and bottom surfaces with points on a user-specified grid. -
Corridor surfaces. A corridor surface is a surface created using data extracted from an underlying corridor model.
