NP5011 is primarily a key to symbols & abbreviations used on Admiralty & International paper & raster charts & leisure folios compiled by the United Kingdom Hydrographic Office (UKHO). Variations may occur on charts adopted into the Admiralty Series that were originally produced by another hydrographic office. Where these symbols & abbreviations are easily understood they are not included as examples in this title. Similarly, symbols & abbreviations shown on Electronic Chart Display & Information Systems (ECDIS) may differ from those described in this book; the key to such symbols is available on NP5012. Revised editions of NP5011 are published as necessary to show symbols which have been newly introduced & to record other developments in charting practice. The more important changes introduced between editions are issued in Admiralty Notices to Mariners as consecutively-numbered updates. On receipt of these updates the appropriate changes should be made as instructed & a record of the update noted in the table included on the inside of the front cover of this title. This edition of NP5011 is based on the