Lesson 6a: Using USGS US Topo and Historic Topographic Maps on your Mobile Device - This video demonstrates how to download and use US Topo and Historic Topographic maps on a mobile device.
What does "georeferenced" mean?
Georeferencing means that the internal coordinate system of a digital map or aerial photo can be related to a ground system of geographic coordinates. A georeferenced digital map or image has been tied to a known Earth coordinate system, so users can determine where every point on the map or aerial photo is located on the Earth's surface.
The relevant coordinate transforms are typically stored within the image file (GeoPDF and GeoTIFF are examples of georeferenced file formats), though there are many possible mechanisms for implementing georeferencing. Georeferencing in the digital file allows basic map analysis to be done, such as pointing and clicking on the map to determine the coordinates of a point, to calculate distances and areas, and to determine other information.
Related
How are different map projections used?
How large is the North American Datum of 1927 (NAD 27) to NAD 83 shift?
What is a geographic information system (GIS)?
What does the term UTM mean? Is UTM better or more accurate than latitude/longitude?

Lesson 6a: Using USGS US Topo and Historic Topographic Maps on your Mobile Device - This video demonstrates how to download and use US Topo and Historic Topographic maps on a mobile device.
The National Elevation Dataset (NED) is the primary elevation data product produced and distributed by the USGS National 3D Elevation Program (3DEP). The NED provides seamless raster elevation data of the conterminous United States, Alaska, Hawaii, and the island territories.
The National Elevation Dataset (NED) is the primary elevation data product produced and distributed by the USGS National 3D Elevation Program (3DEP). The NED provides seamless raster elevation data of the conterminous United States, Alaska, Hawaii, and the island territories.
The Revolution in Mapping at the U.S. Geological Survey
by Susan P. Benjamin, Research Geographer
The Revolution in Mapping at the U.S. Geological Survey
by Susan P. Benjamin, Research Geographer
USGS topographers making an electronic distance measurement in a dry lake bed in Saline Valley in Death Valley, California.
USGS topographers making an electronic distance measurement in a dry lake bed in Saline Valley in Death Valley, California.
Department of the Interior metadata implementation guide—Framework for developing the metadata component for data resource management
US Topo—Topographic maps for the Nation
Topographic map symbols
Georeferenced sea-floor mapping and bottom photography in Long Island Sound
Related
How are different map projections used?
How large is the North American Datum of 1927 (NAD 27) to NAD 83 shift?
What is a geographic information system (GIS)?
What does the term UTM mean? Is UTM better or more accurate than latitude/longitude?

Lesson 6a: Using USGS US Topo and Historic Topographic Maps on your Mobile Device - This video demonstrates how to download and use US Topo and Historic Topographic maps on a mobile device.
Lesson 6a: Using USGS US Topo and Historic Topographic Maps on your Mobile Device - This video demonstrates how to download and use US Topo and Historic Topographic maps on a mobile device.
The National Elevation Dataset (NED) is the primary elevation data product produced and distributed by the USGS National 3D Elevation Program (3DEP). The NED provides seamless raster elevation data of the conterminous United States, Alaska, Hawaii, and the island territories.
The National Elevation Dataset (NED) is the primary elevation data product produced and distributed by the USGS National 3D Elevation Program (3DEP). The NED provides seamless raster elevation data of the conterminous United States, Alaska, Hawaii, and the island territories.
The Revolution in Mapping at the U.S. Geological Survey
by Susan P. Benjamin, Research Geographer
The Revolution in Mapping at the U.S. Geological Survey
by Susan P. Benjamin, Research Geographer
USGS topographers making an electronic distance measurement in a dry lake bed in Saline Valley in Death Valley, California.
USGS topographers making an electronic distance measurement in a dry lake bed in Saline Valley in Death Valley, California.