||It has been suggested that Typographic unit be merged into this article. (Discuss) Proposed since May 2015.|
|352.78×10−6 m||352.778 μm|
|US customary units (Imperial units)|
|1.1574×10−3 ft||13.889×10−3 in|
The point is the smallest whole unit of measure in typography. It is used for measuring font size, leading, and other minute items on a printed page. Different points have been used since the 18th century, with measures varying from 0.18 to 0.4 millimeters. Following the advent of desktop publishing in the 1980s and '90s, the importance of digital printing supplanted the letterpress printing systems around the world and established the DTP point as the de facto standard. This measures 1⁄72 of the international inch (about 0.35 mm) and, as with earlier American points, is considered 1⁄12 of a pica.
In metal type, the point size of the font described the height of the metal body on which the typeface's characters were cast. In digital type, letters of a font are designed around an imaginary space called an "em square". When a point size of a font is specified, the font is scaled so that its em square has a side length of that particular length in points. Although the letters of a font usually fit within the font's em square, there is not necessarily any size relationship between the two, so the point size does not necessarily correspond to any measurement of the size of the letters on the printed page.
A measurement in points can be represented in three different ways. For example, 14 points (1 pica plus 2 points) can be written:
- 1P̸2p (12 points would be just "1P̸")—traditional style
- 1p2 (12 points would be just "1p")—format for desktop
- 14pt (12 points would be "12pt" or "1pc" since it is the same as 1 pica)—format used by Cascading Style Sheets defined by the World Wide Web Consortium
The Truchet point, the first modern typographic point, was 1⁄144 of a French inch or 1⁄1728 of the royal foot. It was invented by the French clergyman Sébastien Truchet. During the metrication of France amid its revolution, a 1799 law declared the meter to be exactly 443.296 French lines long, establishing a length to the royal foot of 9,000⁄27,706 or 0.325 m. This made the Truchet Point equal to 15,625⁄83,124 or 0.187 972 186 mm.
The Fournier point established by Pierre Simon Fournier[when?] was about 11⁄864 French inches or (by 1799) 0.345 mm. This is very close to the present international point described above, but Fournier's point did not achieve lasting popularity despite being revived by the Monotype Corporation in 1927. It became standard in Belgium.
Other French points were subsequently employed, largely owing to the Didot point's unwieldy conversion to metric units. (The divisor of its conversion ratio has the prime factorization of 3 × 7 × 1979.) The standard value in European printers' offices came to be the slightly larger 0.376 065 mm'. Other values included Hermann Berthold's 0.376 mm point, Jan Tschichold's 0.375 94 mm (266 points to 100 mm), and a generally ignored proposal[who?] to use 0.375 mm offered in 1975. The French National Print Office adopted a point of 0.4 mm exactly[when?] and continues to use this measurement today.
The Didot point has been replaced by the DTP point in France and throughout the world.
A typographic or printer's foot contains 72 picas or 864 points. The Metric Act of 1866 established a legal ratio of 1200 : 3937 between the foot and the meter. For the survey foot used prior to 1959, this was 0.0002% more than 304.8 mm, the length of the international foot established by the 1959 International Yard and Pound Agreement.
Another point was proposed[by whom?] to be exactly 996 points or 83 picas in 350 mm, giving it a value around 0.013 848 867 inch (0.351 405 622 mm).
The Johnson point was established by Lawrence Johnson[when?] based on a printer's foot 249⁄250 as large as the standard foot (11.952 inches or 0.996 foot). It thus had a value of 0.0138
3 inch. The 15th meeting of the Type Founders Association of the United States approved the "Johnson pica" as its official standard in 1886. Following the 1959 standardization of the foot, this meant the American printer's foot was 303.5808 mm exactly, giving it a point size of 0.3513 6 mm. This size was used by Donald Knuth's TeX computer typesetting system and is thus sometimes known as the TeX point.
Like the French Didot point, the traditional American printer's point was replaced in the 1980s by the current computer-based DTP point system.
Desktop publishing point
The desktop publishing point (DTP point) or PostScript point is defined as 1⁄72 or 0.0138 of the international inch, making it equivalent to 0.3527 mm. Twelve points make up a pica, and six picas make an inch.
This specification was developed by John Warnock and Charles Geschke when they created Adobe PostScript. It was adopted by Apple Computer as the standard for the display resolution of the original Macintosh desktop computer and the print resolution for the LaserWriter printer.
Fonts originally consisted of a set of moveable type letterpunches purchased from a type foundry. As early as 1600, the sizes of these types—their "bodies"—acquired traditional names in English, French, German, and Dutch, usually from their principal early uses. These names were used relative to the others and their exact length would vary over time, from country to country, and from foundry to foundry. For example, "agate" and "ruby" used to be a single size "agate ruby" of about 5 points; metal type known as "agate" later ranged from 5 to 5.8 points. The sizes were gradually standardized as described above. Modern Chinese typography uses the following names in general preference to stating the number of points. In ambiguous contexts, the word hào (t 號, s 号, lit. "number") is added to the end of the size name to clarify the meaning.
Note that the Chinese font sizes use American points; the Continental systems traditionally used the Fournier or Didot points. The Fournier points, being smaller than Didot's, were associated with the names of the Didot type closest in size rather than identical in number of points.
|Point||American system||Continental system||Chinese system|
|2||Saxon||Non Plus Ultra
|Non plus ultra
|18||Great Primer||Gros-romain||1½ Cicero||Paragon
|22||Double Small Pica||Gros-parangon||二||Èr||"Two"|
|24||Double Pica||Palestine||Doppelcicero||Dubbele cicero
|28||Double English||Petit-canon||Doppelmittel||Dubbele mediaan|
|32||Double Columbian||Kleine Kanon
|36||Double Great Primer||Trismégiste||Kanon
|42||Seven-line Nonpareil||Grobe Kanon||Grote Kanon||初||Chū||"Initial"|
|60||Five-line pica||Grobe Missal||Sabon|
|66||Grobe Sabon||Grote sabon|
|100||Moyenne de fonte|
|108||Nine-line pica||Imperial||9 cicero|
- Phinney, Thomas. "Point Size and the Em Square: Not What People Think". Phinney on Fonts. Retrieved 20 August 2013.
- "15 Fonts". Cascading Style Sheets Level 2 Revision 1 (CSS 2.1) Specification W3C Recommendation 07 June 2011. Retrieved 20 August 2013.
- Public Law 39-183.
- Tucker, H. A. (1988). "Desktop Publishing". In Ruiter, Maurice M. de. Advances in Computer Graphics III. Springer. p. 296. ISBN 3-540-18788-X.
- Spring, Michael B. (1991). Electronic printing and publishing: the document processing revolution. CRC Press. p. 46. ISBN 0-8247-8544-4.
- Southward, John (1888), "Typography", Encyclopædia Britannica, 9th ed., Vol. XXIII, New York: Charles Scribner's Sons, p. 698.
- Romano, Frank (Summer 2009). "The History of the Typographic Point" (PDF). APHA Newsletter (No. 171): 3–4.
- "Type", Sizes.com, Santa Monica: Sizes Inc., 2004.
- Pasko, Wesley Washington, ed. (1894), American Dictionary of Printing and Bookmaking, Containing a History of These Arts in Europe and America, with Definitions of Technical Terms and Biographical Sketches, New York: Howard Lockwood & Co., p. 522.
- Pasko (1894), p. 215.
- Bauer, Friedrich (1929), Die Normung der Buchdrucklettern: Schrifthöhe, Schriftkegel, und Schriftlinie in ihrer geschichtlichen Entwichlung, Leipzig: Deutscher Buchgewerbeverein, p. 64. (German)
- Pasko (1894), p. 18.
- The existence of such small bodies was only notional in the age of metal type.
- Bauer (1934).
- De Vinne (1900), p. 68.
- De Vinne, Theodore Low (1900), The Practice of Typography: A Treatise on the Processes of Type-Making, the Point System, the Names, Sizes, Styles, and Prices of Plain Printing Types, New York: The Century Co., p. 68.
- "minikin, n.¹ and adj.¹", Oxford English Dictionary, 3rd ed., Oxford: Oxford University Press, 2002.
- "excelsior, n."'", Oxford English Dictionary, 1st ed., Oxford: Oxford University Press, 1894.
- Note that the American name for 3-point type was initially "Brilliant" and the English name was initially "Excelsior". The American "Excelsior", meanwhile, was originally 4-point type. The situation subsequently changed.
- Pasko (1894), p. 70.
- "ruby, n.¹", Oxford English Dictionary, 3rd ed., Oxford: Oxford University Press, 2011
- Pasko (1894), p. 11.
- "minionette, n.", Oxford English Dictionary, 3rd ed., Oxford: Oxford University Press, 2002.
- Pasko (1894), p. 65.
- Pronounced "burjoyce".
- Pasko (1894), p. 229.
- The French gros-texte referred indifferently to type sizes between 14 and 16 points.
- Pasko (1894), p. 172.
- Pasko (1894), p. 238.
- von Bauer, Friedrich (1934), Handbuch für Schriftsetzer, Frankfurt: Verlag von Klimsch & Co.. (German)
- Staeck (1980).
- The German Grobe Kanon referred indifferently to 40- or 42-point type.
- The French gros-canon referred indifferently to type sizes of 44 or 48 points.
- Pasko (1894), p. 79.
- Pasko (1894), p. 213.
- Staeck, Erich et al. (1980), Rechenbuch für die Druckindustrie, Itzehoe: Verlag Beruf und Schule, ISBN 3-88013-155-4. (German)