Computers & Writing Systems
SIL’s Private Use Area (PUA)
The SIL PUA committee is no longer functioning. If you wish to see the latest files related to the SIL PUA and the status of encoding in Unicode please visit the new home for the SIL PUA.
SIL PUA Pages
Approximately 248 characters, supporting orthographies in many minority languages, have been approved for assignment to the SIL corporate PUA. Many technical linguistic characters have also been approved. Many of these characters are already supported in current versions of the Encore fonts (SIL fonts) although the Doulos SIL font is the first to contain these in a Unicode encoded font. Future versions will include additional approved characters.
SIL Corporate PUA Documentation
SIL Corporate PUA Assignments
A strategy for deprecating SIL PUA characters
Requesting Additions to SIL’s Private Use Area
SIL Private Use Area Registration Form
Procedure for Registration of SIL Entity Private Use Area Assignments
About the PUA and SIL
The Private Use Area (PUA) is a range of codepoints that are reserved in the Unicode for private-use by software developers and end users who need a special set of characters for their own purposes. There are 6400 PUA code points available in the Basic Multilingual Plane. Unicode also reserves the so-called “supplementary planes” 15 and 16 for private use. The supplementary planes consist of an additional 128K codepoints, but require twice as many bits of information to access them. Click here to go to the SIL PUA Fact Page for additional information.
Although 6400 codepoints may seem like a lot of “code space,” delegates to the 1998 Computer Technical Conference (CTC) realized that this area needs to be managed so that BMP codepoints do not run out in the long term. CTC requested WSTech (which was then known as the NRSI: Non-Roman Script Initiative) to develop a plan for entities to follow. The NRSI’s draft recommendation presented at that conference allows entities to make free use of the lower portion of the PUA range, while the NRSI manages the upper portion for corporation-wide use. The goal of this strategy is to maximize the freedom of SIL field entities to implement needed characters while maintaining a central information repository to ensure consistency of field data and the ability to share and archive data within SIL.
Because of the far-reaching effects of its decisions, the NRSI requested that a committee be set up to provide input from other SIL domains. The PUA Committee was chartered in 2004 to be that advisory body to the NRSI. The committee is made up of members representing various academic domains within SIL. The committee is also the point of contact for SIL members and entities, and other organizations regarding the PUA. The PUA Committee’s goals and responsibilities are officially detailed in the Terms of Reference for the SIL Private Use Area Committee, is operating within the guidelines of the Unicode Technical Committee (UTC) and aims to work in tandem with the UTC.
Contact the PUA committee at: .
Fonts which support the characters in the PUA
Gentium — a typeface for the nations
Industry and the PUA
Handling of PUA Characters in Microsoft Software
Use of the Unicode Private Use Areas by Others
PUA Use in the Adobe Glyph List
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