This document points to resources for the layout and presentation of text in languages that use the Bengali 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 Bengali text.
This document points to resources for Bengali 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 Bengali script. The information here is developed in conjunction with a document that summarises gaps where the Web fails to adequately support the Bengali script.
The editor's draft of this document is being developed in the GitHub repository Indian Language Enablement (iip), 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.
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.
This document was created by Richard Ishida.
See also the GitHub contributors list for the Indian Language Enablement project, and the discussions related to the Bengali script.
This document points to resources for Bengali 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 Bengali script. They include requirements, tests, GitHub discussions, type samples, and more,
The document focuses on typographic layout issues. For a deeper understanding of the Bengali script and how it works see Bangla (Bengali) Orthography Notes, which includes topics such as: Phonology, Vowels, Consonants, Encoding choices, and Numbers.
This document should be used alongside a separate document, Bengali Gap Analysis, which describes gaps in language support for users of the Bengali 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 Bengali 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 Bengali 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 Bengali script. See a list of unresolved questions for Bengali experts. Each section below points to related discussions. See also the repository home page.
The Bengali script is an abugida. Consonants carry an inherent vowel which can be modified by appending vowel signs to the consonant.
The orthographic letters of the Bengali script are derived from Sanskrit, and in some cases don't quite fit the needs of modern Bangla (eg. lack of simple vowels for the sounds ɛ and æ, letters for only 2 of many diphthongs, long and short letters where pronunciation no longer distinguishes those sounds, etc.)
Bengali text runs left to right in horizontal lines. Words are separated by spaces. There are no case distinctions.
The consonant letters are supplemented by repertoire extensions by applying the nukta diacritic to characters.
Consonant clusters at any location are normally indicated using a virama (hasant) between consonants. This results in a large number of conjunct forms expressed using stacked consonants, conjoined consonants, and ligated glyphs. Conjuncts often have different pronunciations than might be expected from the letters involved and, in particular, gemination is very common. Occasionally, a visible virama is used. However, clusters are often not marked at all.
As part of a cluster, RA has special forms, for both cluster-initial and post-base positions.
Word-final consonant sounds may be represented by the special letter ৎ, or by dedicated combining marks (anusvara & visarga), but are generally ordinary consonants that are not marked by a virama.
The Bangla orthography is an abugida with 2 inherent vowels, pronounced ɔ and o. Other post-consonant vowels are written using combining marks (vowel signs) and a specialised use of the y consonant letter.
Vowel harmony plays a significant role in the pronunciation of vowel-related code points in Bangla.
There are pre-base and circumgraph vowel signs. In principle, there are no multipart vowels, however in decomposed text the circumgraphs split into 2 parts each.
Standalone vowels are written using independent vowel letters, one for each vowel sound, including the inherent vowel and diphthongs. The final sound of numerous diphthongs is also represented using independent vowels.
Vowels may be nasalised, using the candrabindu diacritic.
Bengali has native digit shapes.
Underlining is not traditional feature of Bengali text.
tbd