Types of charts used on ships are as follow :
- Admiralty Charts: These charts are published by the hydrographic department of the British Admiralty, under the Hydrographer of the Royal Navy. The policy followed, is to chart all waters, ports and harbours on a scale sufficient for the safe navigation of all the vessels. Elsewhere overseas, Admiralty charts are schemed to enable ships to cross the oceans and proceed along the coasts of the world to reach the approaches of ports, using the most appropriate scales.
- Foreign Charts: In areas not covered by admiralty charts, charts may be published by hydrographer office of the country concerned, giving larger scale coverage than the admiralty charts. The chart Datum of a foreign chart should, carefully be noted as it need not be the same as the Admiralty charts. Position should be transferred from one to the other by bearing and distance from a common feature.
- Australian and New Zealand charts: By arrangement between Australia, New Zealand and the United Kingdom, facsimile copies of selected Australian and New Zealand charts are reprinted by UKHO and form a part of Admiralty series of charts. These charts retain their Australian and New Zealand chart numbers and are corrected by the Australian and New Zealand notices to mariners reprinted in the Admiralty series.
- International charts: These charts cover Large areas. These charts form part of the international series (INT) in which members of the IHO publish charts with internationally agreed limits and scales. Each chart carries a unique INT number in addition to the UKHO national number.
- Decca charts: Are normal charts with Decca Lattice electronically overprinted on it. These charts are prepared for certain coastal area of the world, where a Decca chain is installed. For such areas a non-latticed navigational chart is also available. The number of the Decca chart is the same basic Navigation chart, but is prefixed by “L(D)” followed by the Decca chain number , eg L(D) 3950.
- Loran C Charts: These charts are published by the Admiralty and defence mapping Agency, Washington for areas covered by the Loran C chain. Admiralty Loran C charts retain original BA numbers but are prefixed by L(L-C)
- Omega charts: Omega Lattice maybe overprinted on ocean charts meant for navigation . the charts retain their original number but are prefixed by L(oM).
- Routing charts: These charts provide information regarding current, ice and probable weather for any month, at a glance. This information is very crucial during passage planning. These charts cover different oceans are made to show weather conditions and Load-line zones for each month. They include recommended tracks and distances between ports and fueling terminals, meteorological and ice conditions and ocean currents.