Editing Sea mark (section)

==Definitions==
The [[International Association of Lighthouse Authorities]] defines one system of marks specifying the [[shape]]s, [[colour]]s and [[characteristic light]]s of buoys depending on their purpose, the IALA Maritime Buoyage System.<ref>{{Cite web|last=Mukherjee|first=Paromita|date=January 8, 2021|title=IALA Buoyage System For Mariners – Different Types Of Marks|url=https://www.marineinsight.com/marine-navigation/iala-buoyage-system-for-mariners-types-of-marks/|access-date=2021-03-08|website=Marine Insight}}</ref> For historical reasons, there are two regions of [[lateral mark]]s in use:

* IALA ''Region B'' in the [[Americas]], the [[Philippines]], [[South Korea]] and [[Japan]]
* IALA ''Region A'' everywhere else.

The two regions differ principally in the colours used to denote the two sides of a channel. When approaching a harbour from seaward, ''Region A'' places conical green marks to [[starboard]] and cylindrical red ones to [[port (nautical)|port]]. In ''Region B'' these are replaced with conical red marks to starboard and cylindrical green ones to port. This can be remembered (for ''Region B'') with the [[mnemonic]] ''"Red, right, return"''. Another ''Region B'' mnemonic, which also helps with buoy numbering is "Even Red Left Port" (as in Eric the Red) - Even Numbered buoys are red, on your left (port) side leaving port.  In any case, since in many harbours it is not always apparent which direction is seaward, buoys should be used in connection with the appropriate [[nautical chart]].  Additionally, since marks may be off station due to collision with ships, storms or other factors, they should be used with caution and not relied on solely for [[navigation]]. The two regions are often referred to as two systems, which was the original intent. In 1980 it was decided however to combine these systems and distinguish between regions.<ref>{{cite web | url=http://www.iala-aism.org/web/pages/publications/cadrepubli.html | title=IALA Maritime Buoyage System | publisher=IALA | quote=Cardinal, isolated, safewater, special marks, new dangers, regions A and B | url-status=dead | archive-url=https://web.archive.org/web/20100317153549/http://www.iala-aism.org/web/pages/publications/cadrepubli.html | archive-date=2010-03-17 }}</ref><ref>{{cite web|url=http://www.nauticalissues.com/en/iala.html |title=IALA Maritime Buoyage System |work=Nautical Issues|date=26 June 2023 }}</ref>