Navionics Boating: Difference Between U.S. Government Chart and Navionics Chart Layers

U.S. Government Charts are unaltered nautical charts published by official government sources. They include NOAA Electronic Navigational Charts (ENC) for U.S. coastal and navigable waterways, plus additional shorelines of major lakes and rivers from other public sources. NOAA ENC are vector data sets that conform to the International Hydrographic Office (IHO) S-57 standard. Navionics® Nautical Chart is superior in that they contain greater content, including intricate marina details, port service guides, navigation data at higher zoom levels and Points-of-Interest (POIs). Navionics charts are updated daily reflecting coastline and contour improvements, buoy changes and sand bar shifts, newly marked rocks, submerged structures and new points of interest.