A hydrographic chart is a map that depicts water depths, coastlines, and other relevant information for seafarers. This chart may also be referred to as a nautical chart or a marine chart. The aim of this chart is to provide accurate and detailed navigational information to sailors and other marine travelers. Other synonyms for a hydrographic chart include bathymetric chart, depth chart, sea chart, and nautical map. These terms are often used interchangeably in the marine industry, and they all refer to a map that depicts the depths of the sea and other crucial information for navigation purposes.