Cyrillic Script Resources

W3C Group Draft Note

More details about this document
This version:
https://www.w3.org/TR/2024/DNOTE-cyrl-lreq-20240920/
Latest published version:
https://www.w3.org/TR/cyrl-lreq/
Latest editor's draft:
https://w3c.github.io/eurlreq/cyrl/
History:
https://www.w3.org/standards/history/cyrl-lreq/
Commit history
Editor:
(W3C)
Feedback:
GitHub w3c/eurlreq (pull requests, new issue, open issues)

Abstract

This document points to resources for the layout and presentation of text in languages that use the Cyrillic script. The target audience includes developers of Web standards and technologies, such as HTML, CSS, Mobile Web, Digital Publications, and Unicode, as well as implementers of web browsers, ebook readers, and other applications that need to render Cyrillic text.

Status of This Document

This section describes the status of this document at the time of its publication. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at https://www.w3.org/TR/.

This document points to resources for Cyrillic script layout and text support on the Web and in eBooks. These requirements provide information for Web technologies such as CSS, HTML and digital publications about how to support languages written using the Cyrillic script. The information here is developed in conjunction with a document that summarises gaps where the Web fails to adequately support the Cyrillic script.

The editor's draft of this document is being developed in the GitHub repository European Language Enablement (eurlreq), with contributors from the W3C Internationalization Interest Group. It is published by the Internationalization Working Group. The end target for this document is a Working Group Note.

To make it easier to track comments, please raise separate issues or emails for each comment, and point to the section you are commenting on using a URL.

This document was published by the Internationalization Working Group as a Group Draft Note using the Note track.

Group Draft Notes are not endorsed by W3C nor its Members.

This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

The W3C Patent Policy does not carry any licensing requirements or commitments on this document.

This document is governed by the 03 November 2023 W3C Process Document.

Some links on this page point to repositories or pages to which information will be added over time. Initially, the link may produce no results, but as issues, tests, etc. are created they will show up.

Links that have a gray color led to no content the last time this document was updated. They are still live, however, since relevant content could be added at any time. When the document is updated, links that now point to results will have their live colour restored.

1. Introduction

1.1 Contributors

This document was created by Richard Ishida.

See also the GitHub contributors list for the European Language Enablement project, and the discussions related to the Cyrillic script.

1.2 About this document

This document points to resources for Cyrillic script layout and text support on the Web and in eBooks. These resources provide information for developers of Web technologies such as CSS, HTML and digital publications, and for application developers, about how to support languages written using the Cyrillic script. They include requirements, tests, GitHub discussions, type samples, and more,

The document focuses on typographic layout issues. For a deeper understanding of the Cyrillic script and how it works see Ukrainian Orthography Notes, which includes topics such as: Phonology, Vowels, Consonants, and Numbers.

1.3 Gap analysis

This document should be used alongside a separate document, Cyrillic Gap Analysis, which describes gaps in language support for users of the Cyrillic script, and prioritises and describes the impact of those gaps on the user.

Gap reports are brought to the attention of spec and browser implementers, and are tracked via the Gap Analysis Pipeline. (Filter for Cyrillic script items)

The document Language enablement index points to this document and others, and provides a central location for developers and implementers to find information related to various scripts.

The W3C also has a repository with discussion threads related to the Cyrillic script, including requests from developers to the user community for information about how scripts/languages work, and a notification system that tracks issues in W3C working groups related to the Cyrillic script. See a list of unresolved questions for Cyrillic experts. Each section below points to related discussions. See also the repository home page.

2. Cyrillic Script Overview

The Cyrillic script is an alphabet, ie. a writing system in which both consonants and vowels are indicated. The following overview uses Ukrainian and Russian as example orthographies.

Of the 441 characters in the Unicode Cyrillic blocks, 177 are historic (33%) and 2 are for Lithuanian dialectology. The remaining 262 are just letters – no punctuation, digits, or combining characters. These are all bicameral, which brings the number of distinct modern letters to 131. Although modern Cyrillic text tends to use precomposed forms, rather than combining diacritics separately with base letters, many extended characters are formed by slightly tweaking a set of basic shapes.

Cyrillic text runs left-to-right in horizontal lines. Words are separated by spaces. The visual forms of letters don't usually interact.

The script is bicameral. The shapes of the upper and lowercase forms are typically the same. There can be a significant difference, however, between regular and cursive/italic shapes for the same character.

Modern Ukrainian has 32 basic consonant letters (64 if you include both upper- and lowercase), plus the hard sign and soft sign. Modern Russian has 23 basic consonant letters, including the hard sign and soft sign, and йU+0439 SMALL LETTER SHORT I, which is a semivowel used to write Russian diphthongs. In the absence of an indicator vowel, the soft sign can be used to indicate palatalisation of a consonant.

Ukrainian is written using 10 vowel letters, 4 of which usually indicate palatalisation of the previous consonant. Palatalisation can otherwise be applied or removed using the hard and soft signs. In Russian vowels are written using 10 dedicated vowel letters, half of which usually indicate palatalisation of the previous consonant. They may, however, sometimes be used after one of the few consonants that is always hard, and еU+0435 SMALL LETTER IE is commonly used after non-palatalised consonants in loan words..

There are no special mechanisms to represent standalone vowels. Combining marks are normally not used, and only occur in decomposed text.

Numbers use ASCII digits.

3. All topics

4. Text direction

4.1 Writing mode

5. Glyph shaping & positioning

5.1 Fonts & font styles

5.2 Context-based shaping & positioning

5.3 Letterform slopes, weights, & italics

5.4 Case & other character transforms

6. Typographic units

6.1 Characters & encoding

6.2 Grapheme/word segmentation & selection

7. Punctuation & inline features

7.1 Phrase & section boundaries

7.2 Quotations & citations

7.3 Emphasis & highlighting

7.4 Abbreviation, ellipsis & repetition

7.5 Inline notes & annotations

7.6 Text decoration & other inline features

7.7 Data formats & numbers

8. Line & paragraph layout

8.1 Line breaking & hyphenation

8.2 Text alignment & justification

8.3 Text spacing

8.4 Baselines, line height, etc.

8.5 Lists, counters, etc.

8.6 Styling initials

9. Page & book layout

tbd