History of Inch

	Revision 5 . . December 17, 2001 12:13 pm by Vicki Rosenzweig [copyedit, mostly to fit first sentence to our standard form]
	Revision 4 . . November 27, 2001 10:01 am by (logged).111.13.xxx [more detail on origins of international inch]
	Revision 3 . . October 29, 2001 9:40 am by (logged).111.13.xxx [distinguish survey and international inches]

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Changed: 1c1

Name of several nonmetric units of length.

An inch is any of several relatively short nonmetric? units of length.

Changed: 3c3

Historically, the inch has referred to several slightly different units of length, used in different parts of the world. Today there are two units called the 'inch' still in use, the international inch and the U.S. survey inch, both being largely confined to the United States. Other countries, which previously had their own separate definitions of the inch, have converted to using the metric system instead. When which inch being referred to is not specified, it almost always means the international inch.

Historically, the inch has referred to several slightly different units of length, used in different parts of the world. Today there are two units called the "inch" still in use, the international inch and the U.S. survey inch, both being largely confined to the United States. Other countries, which previously had their own separate definitions of the inch, have converted to using the metric system instead. When the inch being referred to is not specified, it almost always means the international inch.

Changed: 5c5

The international inch is defined as exactly 25.4 mm. This definition was agreed upon by the U.S. and the British Commonwealth in 1958. Prior to that, the U.S. and Canada each had its own, slightly different definition of the inch in terms of metric units, while the U.K. and other Commonwealth countries defined the inch in terms of the [Imperial Standard Yard]?. The definition adopted was the Canadian definition.

The international inch is defined as exactly 25.4 mm. This definition was agreed upon by the U.S. and the British Commonwealth in 1958. Prior to that, the U.S. and Canada each had their own, slightly different definition of the inch in terms of metric units, while the U.K. and other Commonwealth countries defined the inch in terms of the [Imperial Standard Yard]?. The definition adopted was the Canadian definition.