AutoCAD® Civil 3D® 2012 Essentials: Autodesk® Official Training Guide: Essential

What Is Survey Data?

Think back to the last time you played connect-the-dots to draw a picture. Ever wonder who made the dots and how they were made? I'm no expert, but I'm guessing someone took the original picture, laid a piece of tracing paper over it, and made dots along the edges of key features in the picture. Someone skilled at this would make just enough dots to define the features but not so many as to make them confusing or wasteful. The dots are a way of capturing an image and transferring it to another location.

In land development, the land is the picture, and the surveyor is the one who makes the dots—referred to as points. Obviously, tracing paper cannot be used, so the surveyor lays an imaginary grid over the land (a coordinate ...