[2] Vessels have different rights and duties when passing through each area defined by the United Nations Convention on the Law of the Sea (UNCLOS), one of the most ratified treaties.

[3] Normally, the baseline is the low-water line along the coast as marked on large-scale charts that the coastal state recognizes.

In this case, a bay is defined as "a well-marked indentation whose penetration is in such proportion to the width of its mouth as to contain land-locked waters and constitute more than a mere curvature of the coast.

[5]: 51 Territorial sea is a belt of sovereign water that extends at most 12 nautical miles (22 km; 14 mi) from the baseline of a coastal state,[6] including the airspace over and seabed below it.

The contiguous zone is a band of water extending farther from the outer edge of the territorial sea to up to 24 nautical miles (44.4 km; 27.6 mi) from the baseline.

Unlike the territorial sea, there is no standard rule for resolving such conflicts and states must negotiate a compromise.

Before the convention, coastal nations arbitrarily extended their territorial waters to attempt to control activities that are now regulated by the exclusive economic zone, such as offshore oil exploration or fishing rights (see Cod Wars).

The Commission then validates or makes recommendations on the scientific basis for the extended continental shelf claim.

Validated extended continental shelf claims overlapping any demarcation between two or more parties are decided by bilateral or multilateral negotiation, not by the commission.

Originally, this was the distance of a cannon shot, hence the portion of an ocean that a sovereign state could defend from shore.

During the League of Nations Codification Conference in 1930, the issue of establishing international legislation on territorial waters was raised, but no agreement was reached.

[11] Claims by legislation to the adjacent continental shelf and fishing was first made by the United States government immediately following the Second World War.

On 28 September 1945, US President Harry S. Truman issued two proclamations that established government control of natural resources in areas adjacent to the coastline.

[10] It was only at the UNCLOS III (1973-1982) conference, whose provisions did not come into force until 1994, that this issue was resolved at twelve nautical miles.

Pirate radio broadcasting from artificial marine fixtures or anchored ships can be controlled by the affected coastal nation or other nations wherever that broadcast may originate, whether in the territorial sea, exclusive economic zone, the continental shelf or even on the high seas.

Throughout this article, distances measured in nautical miles are exact legal definitions, while those in kilometres are approximate conversions that are not stated in any law or treaty.