The purpose of this document is to set out clearly and simply the essential points of good chart and publication maintenance - both paper and digital.

This document does net attempt to teach navigation. In the case of paper charts and publications, it is assumed that you are able to plot from the text of an Admiralty Notices to Mariners and that you know how to position the updates accurately on the chart.

For the purpose of demonstrating paper chart updating techniques, the examples shown are from charts that were updated by hand in the UK Hydrographic Office.

연도	항행통보 호수	항행통보 항수