Sizes of Type
Type is customarily designed in various standard face sizes. When most printers designed and cast their types in the early days of printing, there was no uniformity of size. The first successful attempt to establish a system of sizes was made by Pierre Simon Fournier in 1737. Fournier's system was based on points. A point was 1/72 of the unit of size he selected.
A point system was officially adopted in 1886 by the United States Typefounders Association. The pica (or 12-point type), selected as the standard, is approximately 1/6 of an inch (0.423 centimeter), and a point is about 1/72 of an inch (0.0353 centimeter).
Measuring Width - Fonts - Type Casting by Hand and by Machine
Invention and Spread of Type and Printing - First Designs for Roman and Italic Types
Old-Style Types by Garamond and Caslon - Bodoni Originates Modern Types