What is the definition or description of: corneal topography?

Its a map : Just as we MAP hills and mountains showing their steepness and elevation. A corneal topography maps the curve and elevation of the coenea.

Corneal curvature: Corneal topography is a sophisticated method of providing a detailed mapping of the curvature or shape of the cornea. Computerized analysis can be used to look for abnormalities, explain vision problems, or evaluate before and after lasik, refractive, or lens implant surgery.