A nautical chart is an essential material not only for the safety of navigation at sea, but also for the research and understanding of the ocean. Paper nautical harts have been used for navigational purposes for several hundreds years, but it was show that paper nautical charts have certain limitations, because the speed of ships has increased dramatically, and Global Positioning Systems (GPS) are now available at sea. Thus, the development of digital charts has been conducted by a number of countries. As a result, the International Hydrographic Organization (IHO) has developed a standard format, Special Publication No. 57 (S-57), as a guideline for the production of electronic navigational charts (ENC). Even though ENCs are a state-of-the-art navigational tool because they are produced on the basis of Geographical Information System (GIS) technology, they can be utilized for various purposes. in this paper, the usage of paper nautical charts, ENCs, and digital charts is reviewed. Also, the various application system that make use of electronic navigational harts and digital charts, as a basic geographical source of information, will be examined on the basis of GIS.