which country's flag is known as the union jack
Union Jack The Union Jack,[note 1][2][3] or Union Flag, is the national flag of the United Kingdom. The flag also has an official or semi-official status in some other Commonwealth realms: for example, it is a ceremonial flag in Canada by parliamentary resolution, and known there as the Royal Union Flag.[4] Further, it is used as an official flag in some of the smaller British overseas territories. The Union Flag also appears in the canton (upper left-hand quarter) of the flags of several nations and territories that are former British possessions or dominions, as well as the state flag of Hawaii.