8. TrueType Open Tag Registry
The Tag Registry defines the TrueType Open tags that Microsoft supports. TrueType Open tags are 4-byte character strings that identify the scripts, language systems, baselines, and features in a TrueType Open font. The registry establishes conventions for naming and using these tags. Registered tags have a specific meaning and convey precise information to developers and text-processing clients of TrueType Open. Microsoft encourages font developers to use registered tags to assure compatibility and ease of use across fonts, applications, and operating systems.
This chapter contains sample sets of commonly used tags for scripts, language systems, and baselines. Microsoft will supply a list of additional tags upon request.
In addition, the Feature Tag section defines all the features and feature tags Microsoft has developed and registered to date. This section includes a description of the function of each feature.
Microsoft expects the list of registered tags and features to expand over time. The most recent version of the registry will be available on Microsoft's ftp and World Wide Web sites, as well as on the quarterly Microsoft Developers Network CD.
Microsoft welcomes nominations for new and useful features to register. For more information about feature and feature tag registration, see the Feature Tag section.