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.
A "centiinch" is not a standard or widely recognized unit of measurement. In the International System of Units (SI), length is typically measured in meters and its subunits, such as centimeters (1 meter = 100 centimeters) and millimeters (1 meter = 1,000 millimeters).
The term "centiinch" appears to be a combination of two different measurement systems. "Centi-" is a prefix used in the metric system to denote a factor of 1/100, while "inch" is a unit of length in the imperial system commonly used in the United States and some other countries.
If someone is using the term "centiinch," it may be intended as a humorous or informal way to express a very small length in a mixed-unit fashion, but it is not part of any standard or recognized system of measurement. To avoid confusion, it's generally best to use established units like centimeters or millimeters when measuring small lengths in the metric system, or inches when using the imperial system.