The word "yard" comes from the Anglo-Saxon word for a straight rod.
A yard has always been 3 feet, although the length of a foot has changed frequently throughout history. In 1959, the International Yard and Pound Agreement was signed between the United Kingdom, South Africa, Australia, the United States, New Zealand and Canada. It was defined as 0.9144 metres. The United States continued to use the old yard under the name 'Survey Yard'
Roadsigns in the United States and the United Kingdom are in miles and yards, rarely in Canada and the Republic of Ireland. It can also be used as a measure of area (square yard) and as a measure of volume (cubic yard). It is also used to measure pitches and fields for a number of sports that originated from English speaking countries. It finds seldom use in other metricated Commonwealth Nations.
Bronze Yard №11, the official standard of length for the United States between 1855 and 1892, when the Treasury Department formally adopted a metric standard. Bronze Yard №11 was forged to be an exact copy of the British Imperial Standard Yard held by Parliament. Both are line standards: the yard was defined by the distance at 62°F between two fine lines drawn on gold plugs (closeup, top) installed in recesses near each end of the bar.
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