ISO IEC 15445-2000 PDF

Full title and description

ISO/IEC 15445:2000 — Information technology — Document description and processing languages — HyperText Markup Language (HTML). This International Standard defines the ISO-adopted form of HTML (commonly referred to as ISO-HTML) as a conforming application of ISO 8879 (SGML) and documents how the HTML language from the W3C HTML 4 family is expressed for use under SGML-based processing and validation.

Abstract

ISO/IEC 15445:2000 provides a formal SGML-based definition (DTD and SGML declaration) of HTML consistent with the W3C HTML 4 recommendations, clarifies conformance classes, and identifies differences and restrictions needed for an SGML-conforming application. It is intended to allow documents to be validated against an ISO-prescribed DTD and to distinguish between conforming and validating systems.

General information

• Status: Published (confirmed international standard).
• Publication date: 2000 (ISO lists publication as May 2000; a corrigendum/corrected version was issued May 2003).
• Publisher: International Organization for Standardization (ISO) / IEC (joint standard, JTC 1/SC 34 responsible).
• ICS / categories: 35.240.30 (IT applications in information, documentation and publishing).
• Edition / version: Edition 1, 2000.
• Number of pages: 20 pages (official ISO publication).

Scope

The scope is a conforming application of ISO 8879 (SGML). ISO/IEC 15445:2000 describes how the HTML language specified by the relevant clauses of the W3C HTML 4 recommendations (HTML 4.0 / HTML 4.01 material) shall be used under SGML and records the specific differences between the W3C text and the ISO-HTML DTD and declarations; material not listed in the scope of the International Standard is excluded. The standard therefore focuses on structure, DTDs, attribute and element usage, character entities and conformance rules for SGML-based processing of HTML content.

Key topics and requirements

• Formal ISO-HTML DTD and SGML declaration that implement HTML 4 semantics under ISO 8879 (SGML).
• Definitions of conformance: conforming documents, validating systems, and conforming systems (distinction between authoring/validator tools and user agents).
• Restricted/required element and attribute usage when operating under SGML (for example strict requirements on document element tags and certain attribute sets).
• Character entity reference handling and character set conformance aligned with the HTML 4 family.
• Guidance on forms, tables, links, images/objects and style sheet interactions where ISO-HTML refines or restricts W3C HTML 4 models to fit SGML processing.

Typical use and users

Authors of SGML-based publishing systems, tool and validator developers, technical writers producing ISO-conforming HTML documents, standards bodies and archives that require a formal SGML-based HTML representation, and organizations that need to validate legacy HTML 4 content against a stable, ISO-prescribed DTD. Browser vendors historically used the distinctions in conformance definitions when implementing user-agent behavior, while authoring tools and validators used the DTD and SGML declaration for checking and transformation pipelines.

Related standards

Key related documents include ISO 8879 (SGML), the W3C Recommendations for HTML 4.0 / HTML 4.01 (normative semantic reference), and other JTC 1/SC 34 outputs and guidance (for document description and processing languages). Later W3C work (XHTML and HTML5) represents the subsequent evolution of web markup beyond the HTML 4 family covered by this ISO standard.

Keywords

ISO-HTML, HTML 4, SGML, DTD, SGML declaration, conformance, validating system, document type definition, HTML 4.01, ISO/IEC JTC 1/SC 34.

FAQ

Q: What is this standard?

A: ISO/IEC 15445:2000 is the ISO/IEC International Standard that defines an SGML-based form of HyperText Markup Language (HTML) — known as ISO-HTML — providing a formal DTD and SGML declaration for HTML as derived from the W3C HTML 4 family.

Q: What does it cover?

A: It covers the SGML-based syntax, DTD parts (entities, element types, attributes), conformance rules (conforming documents vs validating systems), and the specific differences or restrictions needed to use the W3C HTML 4 language under ISO 8879 SGML. It does not attempt to redefine HTML semantics beyond referencing the W3C Recommendation.

Q: Who typically uses it?

A: Validator and authoring-tool developers, organizations with SGML-based publishing workflows, archivists and standards professionals needing a formally specified SGML representation of HTML 4, and anyone requiring strict validation of legacy HTML 4 documents against an ISO-prescribed DTD.

Q: Is it current or superseded?

A: The publication date is 2000 (corrected version issued in 2003). ISO records show the standard was reviewed and confirmed in subsequent systematic reviews (most recently confirmed in 2023), so this 2000 edition remains the ISO/IEC 15445 edition in force unless a future revision is published. Note that the web and W3C have continued evolving HTML (XHTML, HTML5, etc.), but those are separate W3C standards rather than direct revisions of this ISO/IEC text.

Q: Is it part of a series?

A: It is part of ISO/IEC JTC 1/SC 34 work on document description and processing languages and sits alongside other related standards (for example ISO 8879 for SGML). It complements — rather than replaces — W3C HTML recommendations by providing an ISO/SGML binding for HTML 4.

Q: What are the key keywords?

A: ISO-HTML, HTML 4, SGML, DTD, conformance, validating system, ISO/IEC 15445, HTML 4.01.