Frequently Asked Questions

The Unicode Frequently Asked Questions are organized into different topic pages. The list of topic areas is shown below, along with brief explanations of what kinds of questions are answered in each topic area.

Note:

If you have a useful example of a FAQ (with an answer) that you would like to contribute, please send the question and the answer to us. We will consider posting it. If you have general questions, please join the Unicode mailing list and post your questions there.

Many FAQ pages contain links to other pages where you will find further information about specific topics. Check in particular the Basic Questions and Specifications pages.

You may also find it useful to use the search page and type in "solidus FAQ", "BOM FAQ", or "magic wand FAQ" to locate FAQ entries.

The FAQs are collected from many sources. For an explanation, see Attribution.

Click on a topic area to go to that page.

Basic Questions: Discusses the features of Unicode, how it differs from other encodings, and answers basic support questions such as where to find additional information on this site.
Blocks and Ranges: Definitions and usage of Unicode blocks and ranges, and questions about blocks versus script values for characters.
Character Properties, Case Mappings and Names: Answers questions about case conversions and case mappings; also about character names.
Characters and Combining Marks: Discusses a variety of details about text elements, combining characters, compatibility mappings, canonical equivalence...
Chinese and Japanese: Questions specific to Han ideographs, Chinese and Japanese language handling, and East Asian fonts.
CLDR and Locales: Answers questions about Unicode Locales, CLDR, and LDML.
Collation: Answers to questions of sorting and ordering, Unicode and Java.
Compression: The Unicode compression algorithm (SCSU), LZW, Huffman encoding, and others.
Conversions / Mappings: Conversion and mapping to/from other character sets.
Coping with Change: Adapting to changes in the Unicode Standard.
Display of Unsupported Characters: Discusses what to do when attempting to display unsupported Unicode characters.
Entities and Named Sequences: Discusses named entities and Unicode named character sequences.
FAQ on FAQs: Describes how and when new FAQs are created, how FAQs relate to specifications, and and what to do if you think there is an error in a Unicode specification.
Fonts & Keyboards: Where to find more information about fonts. Displaying characters in Java. Glyph variations. Inputting Chinese and other characters.
Greek: Questions specific to the Greek language, script, and fonts.
Guide to Abbreviations in Standards: Lists abbreviations and acronyms used by other standards developing organizations.
Indic Scripts and Languages except Tamil: Questions specific to Indic scripts, languages, fonts, and keyboards.
Internationalization and the Case for Unicode: Explains the role of Unicode in internationalization of software and answers questions about upgrading software to support Unicode.
Internationalized Domain Names (IDN): Provides a series of background explanations about International Domain names and the different specifications for them. (Some content preliminary).
Korean: Questions about Hangul and Jamo characters for Korean, and Korean normalization issues.

Language Tagging: Plane 14 language tags and language tagging in general.
Ligatures, Digraphs and Presentation Forms: Can't find a certain digraph or ligature your language needs? Can you use a particular presentation form?
Line Breaking: Questions about how to break text into separate lines for display.
Middle Eastern Scripts and Languages: Questions about Arabic, Hebrew, and other Middle Eastern scripts.
Normalization: Questions regarding the various normalization forms, their use, and where to go for further information.
Programming Issues: Questions regarding conversion of string handling in old programs, as well as other issues regarding support of Unicode strings in programs.
Proposed New Characters: What are the latest proposals? What about my script? When will the next Unicode book be available?
Security Issues: Does Unicode pose security problems? What can be done about such problems as character spoofing?
Specifications: Information on where to find specifications or guidelines for dealing with different programming tasks in the Unicode Standard and related standards.
Standards Developing Organizations: Describes what SDOs are and how the Unicode Consortium works with them. Answers questions about ISO, IETF, W3C, and the terminology they use.
Submitting Successful Character and Script Proposals: Guidelines on how to write a successful proposal to add new characters or a new script, or to fix a problem in the standard.
Tamil Script and Language: Issues relate to the Tamil language and script
Technical Reports Development Process: Discusses the development and maintenance process for technical reports, including how they are created and archived.
Unicode Character Database: Questions about the Unicode Character Database (UCD).
Unicode and ISO 10646: Relationships between Unicode and ISO working groups, ISO standards. How Unicode differs from 10646.
Unicode and the Web: Unicode in other standards (W3C, IETF, etc). How do deal with numeric character references, Unicode in HTML, etc.
UTF-8, UTF-16, UTF-32 & BOM: Questions about encoding forms (UTF-8, UTF-16, and UTF-32), definitions of a UTF (Unicode Transformation Format), and use of the byte order mark.
Variation Sequences: Answers questions about the meaning, use, and display of variation sequences and selectors.
Writing Direction and BIDI Ordering: Questions about writing direction, particularly "bidi" bidirectional left-right and right-left text.