The North American Vertical Datum of 1988, or NAVD 88, is a geodetic datum used as a reference for measuring elevations in North America. It was established to provide a consistent vertical reference across the continent, replacing the older National Geodetic Vertical Datum of 1929 (NGVD 29). NAVD 88 is based on a network of survey benchmarks and uses precise measurements to define the height of these points relative to sea level. NAVD 88 is crucial for various applications, including engineering, construction, and floodplain management. It helps ensure that elevation data is accurate and reliable, which is essential for mapping, land use planning, and environmental studies.