(DLG) GIS 1. data the geographic and tabular data files obtained from the US Geological Survey (USGS) that may include base categories such as transportation, hydrography, contours, and public land survey boundaries 2. format the formal standards developed and published by the USGS for exchange of cartographic and associated tabular data files —note many non-DLG data may be formatted in DLG format This definition last updated 10/25/2008