A "pica" is a unit of measurement commonly used in typography and desktop publishing to represent the size of text, fonts, and other elements on a printed page. The pica is part of a system of measurement used in the field of typesetting, which involves arranging and designing text for printed materials.
In the pica system:
1 pica (abbreviated as "p") is equal to 12 points. 1 point (abbreviated as "pt") is approximately equal to 1/72nd of an inch.
So, 1 pica is roughly equal to 1/6th of an inch.
This system is based on the traditional point system used in printing, where a point is a very small unit of measurement. Picas and points are still widely used in the design and printing industry, especially when specifying font sizes, line spacing, and other layout details for printed materials like books, magazines, and newspapers.
In digital design and modern desktop publishing software, you can often switch between using picas and points or other units like inches, millimeters, or pixels to set and adjust the layout of text and graphic elements.
In the United States surveying system, an "inch" is a unit of length, but it is not significantly different from the standard inch used in everyday measurements. An inch in U.S. surveying is equal to 1/12th of a foot, just like the standard inch. This means that one U.S. survey inch is approximately equal to 0.0833333 feet or about 2.54 centimeters.
The primary distinction in U.S. surveying is the use of the survey foot, which is defined as exactly 12 survey inches. This slight difference in the definition of the foot and inch in U.S. surveying is used for precise land measurements and surveying work, especially when dealing with large areas of land. However, for most everyday purposes, the standard inch and foot are used in the United States and other countries that employ the imperial system.