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Format

Hypertext Markup Language

Download XML

Summary

Name
Hypertext Markup Language
Version
5
Identifiers
  • PUID: fmt/471
  • MIME: text/html
Description
The HyperText Markup Language (HTML) is a markup language designed for the rendering of information via a web browser. It was originally defined as a highly simplified subset of SGML, but is now an international standard, and is maintained by the World Wide Web Consortium (W3C). A HTML document consists of nested elements, each of which may have attributes and content. It begins with an HTML Document Type declaration. HTML 5 does not explicitly define the HTML version or any Document Type Definition (DTD) within the DOCTYPE tag.
File extensions
htm, html
Source
Digital Preservation Department / The National Archives

Relationships

Has lower priority than
Has priority over

Internal signatures

HTML5 Variant 1

Note
HTML 5 does not explicitly define the HTML version or any Document Type Definition (DTD) within the DOCTYPE tag. An HTML5 DOCTYPE tag may contain an obsolete permitted DOCTYPE string, however this is discouraged. As such the present signature does not cover identification of an HTML5 document that includes this obsolete permitted DOCTYPE string. This signature may be subject to further revision as, at the time of writing, development on the HTML5 standard is still ongoing. Variant 1: <!(DOCTYPE|doctype){0-4}(HTML|html)>

Byte sequences

Min Frag Length
Absolute from BOF
Offset
0
Max offset
1024
Byte Sequence
3C21(444F4354595045|646F6374797065){0-4}(48544D4C|68746D6C)3E
Endianness
None

HTML5 Variant 2

Note
BOF: <!(DOCTYPE|doctype){0-4}(HTML|html){0-4}{SYSTEM|system){0-4}('|")about:legacy-compat('|")>

Byte sequences

Min Frag Length
Absolute from BOF
Offset
0
Max offset
1024
Byte Sequence
3C21(444F4354595045|646F6374797065){0-4}(48544D4C|68746D6C){0-4}(53595354454D|73797374656D){0-4}(27|22)61626F75743A6C65676163792D636F6D706174(27|22)3E
Endianness
None

Changelog

  • Updated in V78

    Release date
    23 September 2014

    Hypertext Markup Language 5: Added MIME type, requested by British Library.

  • Updated in V75

    Release date
    17 July 2014

    Hypertext Markup Language 5: Error corrected in binary signature, submitted by Redaktor.

  • Added in V65

    Release date
    25 October 2012

    HTML5: Signature developed through PRONOM Research.

    HTML5: Outline Entry Added.