Description of DLG layers USGS DLG DATA DLG data files contain selected base catagories of cartographic data in digital form. Each element in the file is represented as a node, an area, or a line.
Nodes define the location of the endpoints of every line.
An area is a portion of the map bounded by lines. A line is an ordered set of points that describes the position and shape of a linear feature on the map. Each map can have as many as eleven overlays, as described below. PLSS data are only collected for areas falling solely, or in part, within the states that were formed from the public domain. The PLSS subdivides the public domain and represents property boundaries or references to property boundaries.