The District of Columbia jurisdiction and administrative boundary. The boundary was identified from public land records and digitized using a combination of sources including the 1995 orthophotographs, planimetric data for roads features, U.S. Geological Survey Digital Raster Graphic quad sheets, and the 1999 planimetrics boundary for the Potomac River.This DC boundary is used for the administration, planning, and management of Washington, D.C. by local DC government agencies, commissions and boards. Other administrative legal boundaries such as DC Wards, Advisory Neighborhood Commissions, and Single Member Districts are nested within the DC Administrative boundary.Orthophotography - a computer-generated image of an aerial photograph in which displacements (distortions) caused by terrain relief and camera tilts have been removed. It combines the image characteristics of a photograph with the geometric qualities of a map. Unlike an aerial photograph, an orthoimage has a uniform scale, so it can be used as a base map onto which other map information is overlaid and created. These images, known as orthophotos or orthoimages, provide a consistent scale that enables accurate representation of the District of Columbia's surface. Source: USGS.govPlanimetrics Data - information that represents the horizontal position of features on the Earth's surface, such as roads, buildings, and bodies of water, without including elevation or relief information. This data is often used in mapping and geographic analysis. Source: wikipedia.orgDigital Raster Graphic (DRG) - a scanned image of a U.S. Geological Survey (USGS) topographic map. The scanned image includes all map collar information. The image inside the map neatline is georeferenced to the surface of the Earth. The DRG can be used to collect, review, and revise other digital data. Source: USGS.gov