PostScript fonts
PostScript fonts are font files encoded in outline font specifications developed by Adobe Systems for professional digital typesetting. This system uses the PostScript file format to encode font information.
"PostScript fonts" may also separately be used to refer to a basic set of fonts included as standards in the PostScript system, such as Times New Roman, Helvetica, and Avant Garde.
History
and [|Type 3] fonts, though introduced by Adobe in 1984 as part of the PostScript page description language, did not see widespread use until March 1985 when the first laser printer to use the PostScript language, the Apple LaserWriter, was introduced.Even then, in 1985, the outline fonts were resident only in the printer, and the screen used bitmap fonts as substitutes for outline fonts.
Although originally part of PostScript, Type 1 fonts used a simplified set of drawing operations compared to ordinary PostScript, but Type 1 fonts added "hints" to help low-resolution rendering. Originally, Adobe kept the details of their hinting scheme undisclosed and used a encryption scheme to protect Type 1 outlines and hints, which still persists today. Despite these measures, Adobe's scheme was quickly reverse-engineered by other players in the industry. Adobe nevertheless required anyone working with Type 1 fonts to license their technology.
Type 3 fonts allowed for all the sophistication of the PostScript language, but without the standardized approach to hinting or an encryption scheme. Other differences further added to the confusion.
The cost of the licensing was considered very high at this time, and Adobe continued to stonewall on more attractive rates. It was this issue that led Apple to design their own system, TrueType, around 1991. Immediately following the announcement of TrueType, Adobe published ”Adobe type 1 font format”, a detailed specification for the format. Font development tools such as Fontographer added the ability to create Type 1 fonts. The Type 2 format has since been used as one basis for the modern OpenType Format.
Technology
By using PostScript language, the glyphs are described with cubic Bézier curves, and thus a single set of glyphs can be resized through simple mathematical transformations, which can then be sent to a PostScript-ready printer. Because the data of Type 1 is a description of the outline of a glyph and not a raster image, Type 1 fonts are commonly referred to as "outline fonts," as opposed to bitmap fonts. For users wanting to preview these typefaces on an electronic display, small versions of a font need extra hints and anti-aliasing to look legible and attractive on screen. This often came in the form of an additional bitmap font of the same typeface, optimized for screen display. Otherwise, in order to preview the Type 1 fonts in typesetting applications, the Adobe Type Manager utility was required.Font type
Type 0
Type 0 is a "composite" font formatas described in the PostScript Language Reference Manual, 2nd Edition. A composite font is composed of a high-level font that references multiple descendant fonts.Type 1
Type 1 is the font format for single-byte digital fonts for use with Adobe Type Manager software and with PostScript printers. It can support font hinting.It was originally a proprietary specification, but Adobe released the specification to third-party font manufacturers provided that all Type 1 fonts adhere to it.
Type 1 fonts are natively supported in macOS, and in Windows 2000 and later via the GDI API.
Adobe announced on 27 January 2021 that they would end support for Type 1 fonts in Adobe products after January 2023. Support for Type 1 fonts in Adobe Photoshop was discontinued with the release of version 23.0 of the product in October 2021.
Type 2
Type 2 is a character string format that offers a compact representation of the character description procedures in an outline font file. The format is designed to be used with the Compact Font Format. The CFF/Type2 format is the basis for Type 1 OpenType fonts, and is used for embedding fonts in Acrobat 3.0 PDF files.Type 3
Type 3 font consists of glyphs defined using the full PostScript language, rather than just a subset. Because of this, a Type 3 font can do some things that Type 1 fonts cannot do, such as specify shading, color, and fill patterns. However, it does not support hinting. Adobe Type Manager did not support Type 3 fonts, and they are not supported as native WYSIWYG fonts on any version of macOS or Windows.Type 4
Type 4 is a format that was used to make fonts for printer font cartridges and for permanent storage on a printer's hard disk. The character descriptions are expressed in the Type 1 format. Adobe does not document this proprietary format.Type 5
Type 5 is similar to the Type 4 format but is used for fonts stored in the ROMs of a PostScript printer. It is also known as CROM font.Types 9, 10, 11
referred them as [|CID] font types 0, 1, and 2 respectively, documented in Adobe supplements. Types 9, 10, and 11 are [|CID-keyed] fonts for storing Types 1, 3, and 42, respectively.Type 14
Type 14, or the Chameleon font format, is used to represent a large number of fonts in a small amount of storage space such as printer ROM. The core set of Chameleon fonts consists of one Master Font, and a set of font descriptors that specify how the Master Font is to be adjusted to give the desired set of character shapes for a specific typeface.Adobe does not document the Type 14 format. It was introduced with PostScript 3 in 1997, and de-emphasized in later years as storage became cheaper.
Type 32
Type 32 is used for downloading bitmap fonts to PostScript interpreters with version number 2016 or greater. The bitmap characters are transferred directly into the interpreter's font cache, thus saving space in the printer's memory.Type 42
The Type 42 font format is a PostScript wrapper around a TrueType font, allowing PostScript-capable printers containing a TrueType rasterizer to print TrueType fonts. Support for multibyte CJK TrueType fonts was added in PostScript version 2015. The out-of-sequence choice of the number 42 is said to be a jesting reference to The Hitchhiker's Guide to the Galaxy, where 42 is the Answer to Life, the Universe, and Everything.Core Font Set
In addition to font types, PostScript specifications also defined the Core Font Set, which dictates the minimum number of fonts, and character sets to be supported by each font.PostScript Level 1
The original PostScript defined 13 font styles which form 4 type families:- Courier
- Helvetica
- Times
- Symbol
PostScript Level 2
- ITC Avant Garde Gothic
- ITC Bookman
- Helvetica
- New Century Schoolbook
- Palatino
- ITC Zapf Chancery
- ITC Zapf Dingbats
PostScript Level 3
In PostScript 3, 136 font styles are specified, which include the 35 font styles defined in PostScript 2, core fonts in popular operating systems, selected fonts from Microsoft Office, and the HP 110 font set. New fonts include:- Albertus
- Antique Olive
- Apple Chancery
- Arial
- Bodoni
- Carta
- Chicago
- Clarendon
- Cooper Black, Cooper Black Italic
- Copperplate Gothic
- Coronet
- Eurostile
- Geneva
- Gill Sans
- Goudy
- Helvetica
- Hoefler Text, Hoefler Ornaments
- Joanna
- Letter Gothic
- ITC Lubalin Graph
- ITC Mona Lisa Recut
- Marigold
- Monaco
- New York
- Optima
- Oxford
- Stempel Garamond
- Tekton
- Times New Roman
- Univers
- Wingdings
Others
However, in recent versions of Adobe Acrobat Reader, Helvetica and Times were internally replaced by Arial and Times New Roman respectively.
Character sets
Although PostScript fonts can contain any character set, there are character sets specifically developed by Adobe, which are used by fonts developed by Adobe.Adobe Western 2
It includes a basic character set containing upper and lowercase letters, figures, accented characters, and punctuation. These fonts also contain currency symbols, standard ligatures, common fractions, common mathematics operators, superscript numerals, common delimiters and conjoiners, and other symbols. Compared to the ISO-Adobe character set, Western 2 also adds 17 additional symbol characters: euro, litre, estimated, omega, pi, partialdiff, delta, product, summation, radical, infinity, integral, approxequal, notequal, lessequal, greaterequal, and lozenge.Fonts with an Adobe Western 2 character set support most western languages including Afrikaans, Basque, Breton, Catalan, Danish, Dutch, English, Finnish, French, Gaelic, German, Icelandic, Indonesian, Irish, Italian, Norwegian, Portuguese, Sami, Spanish, Swahili and Swedish.
This standard superseded ISO-Adobe as the new minimum character set standard as implemented in OpenType fonts from Adobe.