A "point" (abbreviated as "pt") is a unit of measurement commonly used in typography and desktop publishing to specify the size of text, fonts, and other elements on a printed or digital page. The point is part of a system of measurement used in the field of typesetting, which involves arranging and designing text for printed materials.
In the point system:
1 point (abbreviated as "pt") is equal to approximately 1/72nd of an inch. This means that there are approximately 72 points in 1 inch.
Points are used to define the size of fonts, leading (line spacing), and other layout details in printed materials. For example, when you specify a font size of 12 points, you are indicating that the height of the characters in that font will be roughly 1/6th of an inch or about 4.23 millimeters.
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 points and other units like picas, inches, millimeters, or pixels to set and adjust the layout of text and graphic elements.
The term "long reed" does not refer to a standard unit of measurement or a widely recognized term in contemporary systems of measurement. It's possible that "long reed" is used in a specific context or industry, but it does not have a standard definition in general measurements.
If you have more context or specific information about how "long reed" is used, I would be happy to try to provide a more precise explanation.