What is OpenType?
OpenType is a new standard for digital type fonts, developed jointly by Adobe and Microsoft. OpenType supersedes Microsoft's TrueType Open extensions to the TrueType format. OpenType fonts can contain either PostScript or TrueType outlines in a common wrapper. An OpenType font is a single file, which can be used on both Macintosh and Windows platforms without conversion. OpenType fonts have many advantages over previous font formats because they contain more glyphs, support more languages (OpenType uses the Unicode standard for character encoding,) and support rich typographic features such as small caps, old style figures, and ligatures — all in a single font.
Beginning with Adobe InDesign and Adobe Photoshop 6.0, applications have begun to support OpenType layout features. OpenType layout allows you to access features such as old style figures or true small caps by simply applying formatting to text. In most applications that do not actively support such features, OpenType fonts work just like other fonts, although the OpenType layout features are not accessible.
OpenType with PostScript outlines is supported by the latest versions of Adobe Type Manager, and is natively supported in Windows 2000. Apple has also announced its intent to support OpenType, and supplies Japanese system fonts for Mac OS X in OpenType form with PostScript outlines. The OpenType™ format is a superset of the existing TrueType and Adobe PostScript Type 1 font formats. It provides improved cross-platform document portability, rich linguistic support, powerful typographic capabilities, and simplified font management requirements.
OpenType, as jointly defined by Microsoft and Adobe Systems, is technically an extension of Microsoft's TrueType Open format, which can contain either PostScript font outlines (.otf) or TrueType font outlines (.ttf). OpenType .otf fonts are recognized and rendered on-screen by a PostScript rasterizer, such as Adobe Type Manager (ATM), which is either installed as an add-on system software component, or built into some operating systems, such as Microsoft Windows 2000, XP and Macintosh OS X. OpenType fonts peacefully co-exist with current font formats and can be used in the same document alongside Type 1 and TrueType fonts.
What are the advantages of OpenType?
OpenType offers several compelling advantages:
- A single,cross-platform font file that can be used on both Macintosh and Windows platforms
- An expanded character set based on the international Unicode encoding standard for rich linguistic support
- Advanced typographic capabilities related to glyph positioning and glyph substitution that allow for the inclusion of numerous alternate glyphs — such as old-style figures, small capitals and swashes — in one font file
- A compact font outline data structure for smaller font file sizes
- OpenType is natively supported in 2000/XP and the Macintosh OSX operating system
- OpenType advanced typographic features are supported in Adobe InDesign CS all versions and Adobe Photoshop CS all versions
What compression technologies are incorporated in OpenType?
All OpenType fonts with PostScript outlines (.otf) use Compact Font Format (CFF, or Type 2) for considerable size reduction. Although CFF is not strictly compression, since the outlines do not have to be decompressed to be rendered, the result is still more compact than Type 1. Adobe’s OpenType fonts also use subroutinization for additional size reduction. OpenType fonts with TrueType outlines (.ttf) have the option of using compression technology licensed by Microsoft.
Why are there two kinds of OpenType fonts?
The OpenType format is the result of merging two existing formats — Type 1 and TrueType fonts — so it is important to retain the advantages of both.
Can I still use my Type 1 or TrueType fonts if I use OpenType?
You can continue working as you always have. OpenType works seamlessly alongside both TrueType and Type 1 fonts. OpenType fonts simply provide more power, since they offer extended language support and advanced typographic features on platforms and applications that support extended OpenType capabilities.
What does OpenType support mean? If I’m using an operating system that supports OpenType, can I use OpenType features in all my applications?
OpenType support consists of three types: basic OpenType support (the fonts work like any other fonts); Unicode support (access to extended language character sets); and OpenType layout support (support for advanced typographic features). Some operating systems (or operating system extensions) can provide support for one or more of these, but support for Unicode and layout features requires that an application be programmed to provide this functionality. Adobe InDesign (all versions) and Adobe Photoshop 6.0 and later support OpenType advanced typographic features.