NAD 83, or the North American Datum of 1983, is a geodetic datum used for mapping and navigation in North America. It provides a standard reference framework for geographic coordinates, allowing for accurate positioning and data sharing across various applications, including GPS technology. Developed by the National Oceanic and Atmospheric Administration (NOAA), NAD 83 replaced the earlier NAD 27 system. It is based on a more modern ellipsoid model of the Earth, improving accuracy in determining locations. This datum is widely used by government agencies, surveyors, and researchers for various geographic and environmental studies.