PostScript Type 1 (PFB) Font Format

PostScript Type 1, commonly encountered as PFB (Printer Font Binary) files, is a font format developed by Adobe Systems in 1985 as part of the PostScript page description language. For nearly two decades, Type 1 fonts were the professional standard for digital typography, particularly in high-end publishing and commercial printing. The format uses cubic Bézier curves to define glyph outlines, offering superior mathematical precision for complex letterforms.

File Components

Unlike modern font formats that use a single file, PostScript Type 1 fonts require multiple files to function:

• .PFB (Printer Font Binary): Encrypted binary outline data for Windows
• .PFA (Printer Font ASCII): ASCII-encoded outline data for Unix/Mac
• .PFM (Printer Font Metrics): Metrics file for Windows
• .AFM (Adobe Font Metrics): Metrics file for Mac/Unix
• .INF: Installation information (Windows)

Historical Significance

Type 1 fonts revolutionized digital typography in the 1980s and 1990s:

• Enabled the desktop publishing revolution alongside PageMaker and QuarkXPress
• Provided resolution-independent, scalable typography
• Established professional print standards for two decades
• Powered PostScript printers and imagesetters
• Formed the foundation for Adobe's extensive font library

Current Status

In January 2023, Adobe officially announced the end of support for PostScript Type 1 fonts, marking the format's transition to legacy status after nearly 40 years. Adobe ceased technical support, and modern applications have largely removed Type 1 compatibility. The industry has standardized on OpenType, which offers all of Type 1's capabilities plus extensive additional features.

The PostScript Type 1 font format represents one of the most consequential developments in digital typography history. Its nearly 40-year reign shaped professional publishing, defined quality standards, and ultimately paved the way for modern font technologies. Understanding this history illuminates both the triumphs and limitations of proprietary font standards.

PostScript Origins (1982-1984)

Before PostScript Type 1 fonts, there was PostScript itself—a revolutionary page description language developed by Adobe founders John Warnock and Charles Geschke:

Adobe developed PostScript as a device-independent page description language, initially for Xerox. When Xerox declined to commercialize it, Warnock and Geschke founded Adobe Systems in 1982 to pursue the technology independently.

The Birth of Type 1 (1984-1985)

In 1984, Adobe partnered with Apple to develop the LaserWriter, the first PostScript-based laser printer. This collaboration necessitated a scalable font format:

• 1984: Initial PostScript font format developed for LaserWriter
• 1985: PostScript Type 1 specification formalized
• March 1985: Apple LaserWriter ships with 35 PostScript fonts
• Key innovation: Cubic Bézier curves for mathematically precise outlines
• Quality advantage: Superior to bitmap fonts at any resolution

The LaserWriter's success demonstrated that affordable, professional-quality printing was achievable. Combined with Aldus PageMaker (1985), this launched the desktop publishing revolution.

Desktop Publishing Revolution (1985-1990)

Type 1 fonts became the cornerstone of professional publishing:

Adobe initially kept the Type 1 specification proprietary, licensing it to select font vendors. This exclusivity, while protecting Adobe's business, frustrated the broader industry and set the stage for competition.

The TrueType Challenge (1991-1993)

Apple and Microsoft, frustrated by Adobe's licensing terms and the need for Adobe Type Manager, developed a competing format:

Facing TrueType competition, Adobe made a strategic decision in 1990 to publish the Type 1 specification, opening the format to any font foundry. This move democratized high-quality font creation but couldn't prevent TrueType's rise in consumer markets.

The Multiple Master Experiment (1991-1999)

Adobe attempted to extend Type 1 with Multiple Master (MM) technology:

• Innovation: Single font with interpolation axes (weight, width, optical size)
• Ahead of its time: Conceptually similar to modern variable fonts
• Limited adoption: Complex for designers, poor software support
• Discontinued 1999: Adobe abandoned the format
• Legacy: Influenced OpenType variable fonts (2016)

Multiple Master fonts demonstrated Adobe's innovation but also the limitations of extending a fundamentally constrained format. The industry needed something new.

OpenType Transition (1996-2005)

The Adobe-Microsoft OpenType collaboration began the end of Type 1's dominance:

The Long Twilight (2010-2023)

Even as OpenType became standard, Type 1 fonts persisted in legacy workflows:

• Archival projects: Old documents requiring original fonts
• Print service providers: Maintaining compatibility with old files
• Specialized software: CAD, mapping, and engineering applications
• Institutional inertia: Organizations resistant to font migration

Adobe maintained Type 1 support to avoid breaking customer workflows, but the format received no new development or improvements for over a decade.

End of Life Announcement (2023)

In January 2023, Adobe formally ended the Type 1 era:

Modern operating systems have also reduced or removed Type 1 support:

• macOS Catalina (2019): Warning messages for Type 1 fonts
• macOS Big Sur (2020): Type 1 fonts no longer install easily
• Windows 11: Limited Type 1 support, OpenType preferred
• Modern Linux: Type 1 requires legacy font rendering packages

Legacy and Impact (2025 and Beyond)

PostScript Type 1's 38-year run left an indelible mark on digital typography:

Today, Type 1 fonts exist primarily in archives, legacy document workflows, and historical collections. For any active typography work, OpenType fonts offer everything Type 1 provided plus decades of additional innovation. The format that defined professional digital typography for a generation has completed its journey from revolution to legacy.

PostScript Type 1 fonts use a sophisticated but constrained technical architecture designed for the PostScript imaging model and 1980s computing environments.

Outline Technology

Type 1 fonts define glyph shapes using cubic Bézier curves:

File Format

Encryption

Type 1 fonts use a simple encryption scheme (eexec) to protect font data:

• Purpose: Prevent casual copying and modification
• Algorithm: XOR cipher with fixed key (not secure by modern standards)
• Effectiveness: Easily circumvented, primarily psychological deterrent
• Legacy impact: Complicates font conversion and archiving

Character Encoding

Type 1's 256-glyph limitation created significant encoding challenges:

Hinting

Type 1 includes sophisticated hinting for low-resolution output:

• Stem hints: Maintain consistent stroke widths
• Alignment zones: Align overshoots, baselines, x-height
• Blue values: Key vertical alignment positions
• Flex hints: Handle curves near vertical/horizontal
• Limitation: Less sophisticated than TrueType grid-fitting

PFB files use a segmented binary structure with clear ASCII and binary sections:

PFB Segments

Required Font Dictionary Entries

%!PS-AdobeFont-1.0: FontName 001.000
%%CreationDate: 1990:01:15
%%VMusage: 12000 20000
11 dict begin
/FontInfo 9 dict dup begin
  /version (001.000) readonly def
  /FullName (Font Name) readonly def
  /FamilyName (Family) readonly def
  /Weight (Medium) readonly def
  /ItalicAngle 0 def
  /isFixedPitch false def
  /UnderlinePosition -100 def
  /UnderlineThickness 50 def
end readonly def
/FontName /FontName def
/PaintType 0 def
/FontType 1 def
/FontMatrix [0.001 0 0 0.001 0 0] readonly def
/Encoding StandardEncoding def
/FontBBox {-180 -250 1000 850} readonly def
/UniqueID 12345 def
currentdict end
currentfile eexec
[encrypted binary data follows...]

AFM File Structure

Adobe Font Metrics files provide human-readable metrics data:

StartFontMetrics 4.1
FontName MyFont-Regular
FullName My Font Regular
FamilyName My Font
Weight Regular
ItalicAngle 0
IsFixedPitch false
UnderlinePosition -100
UnderlineThickness 50
Version 001.000
Notice Copyright (c) 1990
EncodingScheme AdobeStandardEncoding
CapHeight 700
XHeight 450
Ascender 800
Descender -200
StartCharMetrics 256
C 32 ; WX 250 ; N space ; B 0 0 0 0 ;
C 65 ; WX 667 ; N A ; B 0 0 667 700 ;
C 66 ; WX 667 ; N B ; B 100 0 600 700 ;
...
EndCharMetrics
StartKernPairs 150
KPX A V -50
KPX V A -50
...
EndKernPairs
EndFontMetrics

Typography Features

Critical Limitations

• 256 glyphs maximum: Insufficient for multilingual or extended character sets
• No Unicode: Platform-specific encodings created compatibility nightmares
• Multiple files: Easy to lose companion metrics files
• Platform fragmentation: Different formats for Mac/Windows
• No OpenType features: Required separate fonts for typographic variants
• Weak encryption: Provided minimal protection
• Limited hinting: Inferior to TrueType for screen display

Historical Usage (1985-2010)

Type 1 fonts dominated professional publishing for 25 years:

• Book and magazine publishing
• Commercial printing and prepress
• Corporate identity and branding
• Advertising and graphic design
• Professional typography and typesetting
• PostScript RIP (Raster Image Processor) workflows

Legacy Contexts (2010-2023)

Type 1 persisted in specific scenarios:

• Document archives: Maintaining original font rendering in old files
• Print service bureaus: Supporting legacy customer files
• Specialized software: CAD, GIS, and engineering applications
• Legacy RIP systems: Older PostScript imagesetters
• Font licensing: Some vendors never converted libraries

Current Reality (2025)

Type 1 fonts should not be used in any active workflow:

• Adobe Creative Cloud: No Type 1 support since 2023
• Modern operating systems: Limited or no Type 1 support
• Web use: Never supported; use WOFF2
• Font vendors: No longer distribute Type 1 fonts
• Conversion required: Migrate all Type 1 fonts to OpenType

Modern font formats offer significant advantages over Type 1:

Type 1 to OpenType Migration

OpenType CFF (with PostScript outlines) is the natural successor:

• Preserves outline quality: Cubic Bézier curves retained
• Single file: No separate metrics files
• 65,536+ glyphs: Supports comprehensive character sets
• Unicode encoding: Universal character access
• OpenType features: Ligatures, alternates, small caps
• Cross-platform: Single font for Mac/Windows/Linux

Converting Type 1 to OpenType

Professional conversion workflow:

# Command-line conversion
fontforge -c '
Open("myfont.pfb")
Reencode("unicode")
Generate("myfont.otf")
'

# Or batch convert multiple fonts
for pfb in *.pfb; do
  fontforge -c "
    Open(\"$pfb\")
    Reencode(\"unicode\")
    Generate(\"${pfb%.pfb}.otf\")
  "
done

Conversion Checklist

• Verify metrics: Compare converted font against original
• Check kerning: Ensure kerning pairs transferred correctly
• Test rendering: Verify output in target applications
• Validate encoding: Confirm Unicode mapping accuracy
• Review licensing: Ensure conversion rights
• Document changes: Note any conversion issues

Legacy Installation (Not Recommended)

For historical reference only—do not install Type 1 fonts on modern systems:

Tools and Resources

• FontLab: Professional font editor with Type 1 import
• FontForge: Free, open-source conversion tool
• AFDKO: Adobe Font Development Kit for OpenType
• TransType: Batch font conversion utility
• Font Converter Tool: Our online converter