Abstract

This document is a strict subset of the HTML5 specification that omits user-agent (UA) implementation details. It is targeted toward Web authors and others who are not UA implementors and who want a view of the HTML specification that focuses more precisely on details relevant to using the HTML language to create Web documents and Web applications. Because this document does not provide implementation conformance criteria, UA implementors should not rely on it, but should instead refer to the full HTML5 specification.

This document is an automated redaction of the full HTML5 full HTML5 specification. As such, the two documents are supposed to agree on normative matters concerning Web authors. However, if the documents disagree, this is a bug in the redaction process and the unredacted full HTML specification takes precedence. Readers are encouraged to report such discrepancies as bugs in the bug tracking system of the HTML Working Group.

Status of This document

This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the most recently formally published revision of this technical report can be found in the W3C technical reports index at http://www.w3.org/TR/.

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The publication of this document by the W3C as a W3C First Public Working Draft does not imply that all of the participants in the W3C HTML working group endorse the contents of the specification. Indeed, for any section of the specification, one can usually find many members of the working group or of the W3C as a whole who object strongly to the current text, the existence of the section at all, or the idea that the working group should even spend time discussing the concept of that section.

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The W3C HTML Working Group is the W3C working group responsible for this specification's progress along the W3C Recommendation track. This specification is the 05 July 2011 First Public Working Draft.

Work on this specification is also done at the WHATWG. The W3C HTML working group actively pursues convergence with the WHATWG, as required by the W3C HTML working group charter.

This document was produced by a group operating under the 5 February 2004 W3C Patent Policy. W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.

Table of Contents

  1. 1 Introduction
    1. 1.1 Background
    2. 1.2 Audience
    3. 1.3 Scope
    4. 1.4 History
    5. 1.5 Design notes
      1. 1.5.1 Serializability of script execution
      2. 1.5.2 Compliance with other specifications
    6. 1.6 HTML vs XHTML
    7. 1.7 Structure of this specification
      1. 1.7.1 How to read this specification
      2. 1.7.2 Typographic conventions
    8. 1.8 A quick introduction to HTML
    9. 1.9 Conformance requirements for authors
      1. 1.9.1 Presentational markup
      2. 1.9.2 Syntax errors
      3. 1.9.3 Restrictions on content models and on attribute values
    10. 1.10 Recommended reading
  2. 2 Common infrastructure
    1. 2.1 Terminology
      1. 2.1.1 Resources
      2. 2.1.2 XML
      3. 2.1.3 DOM trees
      4. 2.1.4 Scripting
      5. 2.1.5 Plugins
      6. 2.1.6 Character encodings
    2. 2.2 Conformance requirements
      1. 2.2.3 Extensibility
    3. 2.3 Case-sensitivity and string comparison
    4. 2.5 Common microsyntaxes
      1. 2.5.2 Boolean attributes
      2. 2.5.3 Keywords and enumerated attributes
      3. 2.5.4 Numbers
        1. 2.5.4.1 Non-negative integers
        2. 2.5.4.2 Signed integers
        3. 2.5.4.3 Real numbers
        4. 2.5.4.5 Lists of integers
      4. 2.5.5 Dates and times
        1. 2.5.5.1 Months
        2. 2.5.5.2 Dates
        3. 2.5.5.3 Times
        4. 2.5.5.4 Local dates and times
        5. 2.5.5.5 Global dates and times
        6. 2.5.5.6 Weeks
        7. 2.5.5.7 Vaguer moments in time
      5. 2.5.6 Colors
      6. 2.5.7 Space-separated tokens
      7. 2.5.8 Comma-separated tokens
      8. 2.5.9 References
      9. 2.5.10 Media queries
    5. 2.6 URLs
      1. 2.6.1 Terminology
      2. 2.6.3 Resolving URLs
      3. 2.6.6 Interfaces for URL manipulation
    6. 2.8 Common DOM interfaces
      1. 2.8.1 Reflecting content attributes in IDL attributes
      2. 2.8.2 Collections
        1. 2.8.2.1 HTMLCollection
        2. 2.8.2.2 HTMLAllCollection
        3. 2.8.2.3 HTMLFormControlsCollection
        4. 2.8.2.4 HTMLOptionsCollection
      3. 2.8.3 DOMTokenList
      4. 2.8.4 DOMSettableTokenList
      5. 2.8.6 DOMStringMap
      6. 2.8.7 DOM feature strings
      7. 2.8.8 Exceptions
    7. 2.9 Namespaces
  3. 3 Semantics, structure, and APIs of HTML documents
    1. 3.1 Documents
      1. 3.1.1 Documents in the DOM
      2. 3.1.2 Security
      3. 3.1.3 Resource metadata management
      4. 3.1.4 DOM tree accessors
      5. 3.1.5 Creating documents
    2. 3.2 Elements
      1. 3.2.1 Semantics
      2. 3.2.2 Elements in the DOM
      3. 3.2.3 Global attributes
        1. 3.2.3.1 The id attribute
        2. 3.2.3.2 The title attribute
        3. 3.2.3.3 The lang and xml:lang attributes
        4. 3.2.3.4 The xml:base attribute (XML only)
        5. 3.2.3.5 The dir attribute
        6. 3.2.3.6 The class attribute
        7. 3.2.3.7 The style attribute
        8. 3.2.3.8 Embedding custom non-visible data with the data-* attributes
      4. 3.2.4 Element definitions
        1. 3.2.4.1 Attributes
      5. 3.2.5 Content models
        1. 3.2.5.1 Kinds of content
          1. 3.2.5.1.1 Metadata content
          2. 3.2.5.1.2 Flow content
          3. 3.2.5.1.3 Sectioning content
          4. 3.2.5.1.4 Heading content
          5. 3.2.5.1.5 Phrasing content
          6. 3.2.5.1.6 Embedded content
          7. 3.2.5.1.7 Interactive content
        2. 3.2.5.2 Transparent content models
        3. 3.2.5.3 Paragraphs
      6. 3.2.6 Requirements relating to bidirectional-algorithm formatting characters
      7. 3.2.7 WAI-ARIA
    3. 3.3 APIs in HTML documents
    4. 3.5 Dynamic markup insertion
      1. 3.5.1 Opening the input stream
      2. 3.5.2 Closing the input stream
      3. 3.5.3 document.write()
      4. 3.5.4 document.writeln()
      5. 3.5.5 innerHTML
      6. 3.5.6 outerHTML
      7. 3.5.7 insertAdjacentHTML()
  4. 4 The elements of HTML
    1. 4.1 The root element
      1. 4.1.1 The html element
    2. 4.2 Document metadata
      1. 4.2.1 The head element
      2. 4.2.2 The title element
      3. 4.2.3 The base element
      4. 4.2.4 The link element
      5. 4.2.5 The meta element
        1. 4.2.5.1 Standard metadata names
        2. 4.2.5.2 Other metadata names
        3. 4.2.5.3 Pragma directives
        4. 4.2.5.4 Other pragma directives
        5. 4.2.5.5 Specifying the document's character encoding
      6. 4.2.6 The style element
      7. 4.2.7 Styling
    3. 4.3 Scripting
      1. 4.3.1 The script element
        1. 4.3.1.1 Scripting languages
        2. 4.3.1.2 Restrictions for contents of script elements
        3. 4.3.1.3 Inline documentation for external scripts
      2. 4.3.2 The noscript element
    4. 4.4 Sections
      1. 4.4.1 The body element
      2. 4.4.2 The section element
      3. 4.4.3 The nav element
      4. 4.4.4 The article element
      5. 4.4.5 The aside element
      6. 4.4.6 The h1, h2, h3, h4, h5, and h6 elements
      7. 4.4.7 The hgroup element
      8. 4.4.8 The header element
      9. 4.4.9 The footer element
      10. 4.4.10 The address element
      11. 4.4.11 Headings and sections
        1. 4.4.11.1 Creating an outline
    5. 4.5 Grouping content
      1. 4.5.1 The p element
      2. 4.5.2 The hr element
      3. 4.5.3 The pre element
      4. 4.5.4 The blockquote element
      5. 4.5.5 The ol element
      6. 4.5.6 The ul element
      7. 4.5.7 The li element
      8. 4.5.8 The dl element
      9. 4.5.9 The dt element
      10. 4.5.10 The dd element
      11. 4.5.11 The figure element
      12. 4.5.12 The figcaption element
      13. 4.5.13 The div element
    6. 4.6 Text-level semantics
      1. 4.6.1 The a element
      2. 4.6.2 The em element
      3. 4.6.3 The strong element
      4. 4.6.4 The small element
      5. 4.6.5 The s element
      6. 4.6.6 The cite element
      7. 4.6.7 The q element
      8. 4.6.8 The dfn element
      9. 4.6.9 The abbr element
      10. 4.6.10 The time element
      11. 4.6.11 The code element
      12. 4.6.12 The var element
      13. 4.6.13 The samp element
      14. 4.6.14 The kbd element
      15. 4.6.15 The sub and sup elements
      16. 4.6.16 The i element
      17. 4.6.17 The b element
      18. 4.6.18 The u element
      19. 4.6.19 The mark element
      20. 4.6.20 The ruby element
      21. 4.6.21 The rt element
      22. 4.6.22 The rp element
      23. 4.6.23 The bdi element
      24. 4.6.24 The bdo element
      25. 4.6.25 The span element
      26. 4.6.26 The br element
      27. 4.6.27 The wbr element
      28. 4.6.28 Usage summary
    7. 4.7 Edits
      1. 4.7.1 The ins element
      2. 4.7.2 The del element
      3. 4.7.3 Attributes common to ins and del elements
      4. 4.7.4 Edits and paragraphs
      5. 4.7.5 Edits and lists
    8. 4.8 Embedded content
      1. 4.8.1 The img element
        1. 4.8.1.1 Requirements for providing text to act as an alternative for images
          1. 4.8.1.1.1 General guidelines
          2. 4.8.1.1.2 A link or button containing nothing but the image
          3. 4.8.1.1.3 A phrase or paragraph with an alternative graphical representation: charts, diagrams, graphs, maps, illustrations
          4. 4.8.1.1.4 A short phrase or label with an alternative graphical representation: icons, logos
          5. 4.8.1.1.5 Text that has been rendered to a graphic for typographical effect
          6. 4.8.1.1.6 A graphical representation of some of the surrounding text
          7. 4.8.1.1.7 A purely decorative image that doesn't add any information
          8. 4.8.1.1.8 A group of images that form a single larger picture with no links
          9. 4.8.1.1.9 A group of images that form a single larger picture with links
          10. 4.8.1.1.10 A key part of the content
          11. 4.8.1.1.11 An image not intended for the user
      2. 4.8.2 The iframe element
      3. 4.8.3 The embed element
      4. 4.8.4 The object element
      5. 4.8.5 The param element
      6. 4.8.6 The video element
      7. 4.8.7 The audio element
      8. 4.8.8 The source element
      9. 4.8.9 The track element
      10. 4.8.10 Media elements
        1. 4.8.10.1 Error codes
        2. 4.8.10.2 Location of the media resource
        3. 4.8.10.3 MIME types
        4. 4.8.10.4 Network states
        5. 4.8.10.5 Loading the media resource
        6. 4.8.10.6 Offsets into the media resource
        7. 4.8.10.7 The ready states
        8. 4.8.10.8 Playing the media resource
        9. 4.8.10.9 Seeking
        10. 4.8.10.10 Media resources with multiple media tracks
          1. 4.8.10.10.1 TrackList objects
          2. 4.8.10.10.2 Selecting specific audio and video tracks declaratively
        11. 4.8.10.11 Synchronising multiple media elements
          1. 4.8.10.11.1 Introduction
          2. 4.8.10.11.2 Media controllers
          3. 4.8.10.11.3 Assigning a media controller declaratively
        12. 4.8.10.12 Timed text tracks
          1. 4.8.10.12.1 Text track model
          2. 4.8.10.12.2 Sourcing in-band text tracks
          3. 4.8.10.12.4 Text track API
        13. 4.8.10.13 User interface
        14. 4.8.10.14 Time ranges
        15. 4.8.10.15 Event summary
        16. 4.8.10.17 Best practices for authors using media elements
      11. 4.8.11 The canvas element
      12. 4.8.12 The map element
      13. 4.8.13 The area element
      14. 4.8.14 Image maps
      15. 4.8.15 MathML
      16. 4.8.16 SVG
      17. 4.8.17 Dimension attributes
    9. 4.9 Tabular data
      1. 4.9.1 The table element
        1. 4.9.1.1 Techniques for describing tables
        2. 4.9.1.2 Techniques for table layout
      2. 4.9.2 The caption element
      3. 4.9.3 The colgroup element
      4. 4.9.4 The col element
      5. 4.9.5 The tbody element
      6. 4.9.6 The thead element
      7. 4.9.7 The tfoot element
      8. 4.9.8 The tr element
      9. 4.9.9 The td element
      10. 4.9.10 The th element
      11. 4.9.11 Attributes common to td and th elements
      12. 4.9.13 Examples
    10. 4.10 Forms
      1. 4.10.1 Introduction
        1. 4.10.1.1 Writing a form's user interface
        2. 4.10.1.2 Implementing the server-side processing for a form
        3. 4.10.1.3 Configuring a form to communicate with a server
        4. 4.10.1.4 Client-side form validation
      2. 4.10.2 Categories
      3. 4.10.3 The form element
      4. 4.10.4 The fieldset element
      5. 4.10.5 The legend element
      6. 4.10.6 The label element
      7. 4.10.7 The input element
        1. 4.10.7.1 States of the type attribute
          1. 4.10.7.1.1 Hidden state
          2. 4.10.7.1.2 Text state and Search state
          3. 4.10.7.1.3 Telephone state
          4. 4.10.7.1.4 URL state
          5. 4.10.7.1.5 E-mail state
          6. 4.10.7.1.6 Password state
          7. 4.10.7.1.7 Date and Time state
          8. 4.10.7.1.8 Date state
          9. 4.10.7.1.9 Month state
          10. 4.10.7.1.10 Week state
          11. 4.10.7.1.11 Time state
          12. 4.10.7.1.12 Local Date and Time state
          13. 4.10.7.1.13 Number state
          14. 4.10.7.1.14 Range state
          15. 4.10.7.1.15 Color state
          16. 4.10.7.1.16 Checkbox state
          17. 4.10.7.1.17 Radio Button state
          18. 4.10.7.1.18 File Upload state
          19. 4.10.7.1.19 Submit Button state
          20. 4.10.7.1.20 Image Button state
          21. 4.10.7.1.21 Reset Button state
          22. 4.10.7.1.22 Button state
        2. 4.10.7.2 Common input element attributes
          1. 4.10.7.2.1 The autocomplete attribute
          2. 4.10.7.2.2 The dirname attribute
          3. 4.10.7.2.3 The list attribute
          4. 4.10.7.2.4 The readonly attribute
          5. 4.10.7.2.5 The size attribute
          6. 4.10.7.2.6 The required attribute
          7. 4.10.7.2.7 The multiple attribute
          8. 4.10.7.2.8 The maxlength attribute
          9. 4.10.7.2.9 The pattern attribute
          10. 4.10.7.2.10 The min and max attributes
          11. 4.10.7.2.11 The step attribute
          12. 4.10.7.2.12 The placeholder attribute
        3. 4.10.7.3 Common input element APIs
      8. 4.10.8 The button element
      9. 4.10.9 The select element
      10. 4.10.10 The datalist element
      11. 4.10.11 The optgroup element
      12. 4.10.12 The option element
      13. 4.10.13 The textarea element
      14. 4.10.14 The keygen element
      15. 4.10.15 The output element
      16. 4.10.16 The progress element
      17. 4.10.17 The meter element
      18. 4.10.18 Association of controls and forms
      19. 4.10.19 Attributes common to form controls
        1. 4.10.19.1 Naming form controls
        2. 4.10.19.2 Enabling and disabling form controls
        3. 4.10.19.4 Autofocusing a form control
        4. 4.10.19.5 Limiting user input length
        5. 4.10.19.6 Form submission
        6. 4.10.19.7 Submitting element directionality
      20. 4.10.20 APIs for the text field selections
      21. 4.10.21 Constraints
        1. 4.10.21.1 Definitions
        2. 4.10.21.3 The constraint validation API
        3. 4.10.21.4 Security
      22. 4.10.22 Form submission
        1. 4.10.22.6 Multipart form data
    11. 4.11 Interactive elements
      1. 4.11.1 The details element
      2. 4.11.2 The summary element
      3. 4.11.3 The command element
      4. 4.11.4 The menu element
        1. 4.11.4.1 Introduction
        2. 4.11.4.3 Context menus
      5. 4.11.5 Commands
    12. 4.12 Links
      1. 4.12.1 Introduction
      2. 4.12.2 Links created by a and area elements
      3. 4.12.4 Link types
        1. 4.12.4.1 Link type "alternate"
        2. 4.12.4.2 Link type "author"
        3. 4.12.4.3 Link type "bookmark"
        4. 4.12.4.4 Link type "external"
        5. 4.12.4.5 Link type "help"
        6. 4.12.4.6 Link type "icon"
        7. 4.12.4.7 Link type "license"
        8. 4.12.4.8 Link type "nofollow"
        9. 4.12.4.9 Link type "noreferrer"
        10. 4.12.4.10 Link type "pingback"
        11. 4.12.4.11 Link type "prefetch"
        12. 4.12.4.12 Link type "search"
        13. 4.12.4.13 Link type "sidebar"
        14. 4.12.4.14 Link type "stylesheet"
        15. 4.12.4.15 Link type "tag"
        16. 4.12.4.16 Sequential link types
          1. 4.12.4.16.1 Link type "next"
          2. 4.12.4.16.2 Link type "prev"
        17. 4.12.4.17 Other link types
    13. 4.13 Common idioms without dedicated elements
      1. 4.13.1 The main part of the content
      2. 4.13.2 Bread crumb navigation
      3. 4.13.3 Tag clouds
      4. 4.13.4 Conversations
      5. 4.13.5 Footnotes
  5. 5 Loading Web pages
    1. 5.1 Browsing contexts
      1. 5.1.1 Nested browsing contexts
        1. 5.1.1.1 Navigating nested browsing contexts in the DOM
      2. 5.1.2 Auxiliary browsing contexts
        1. 5.1.2.1 Navigating auxiliary browsing contexts in the DOM
      3. 5.1.3 Secondary browsing contexts
      4. 5.1.6 Browsing context names
    2. 5.2 The Window object
      1. 5.2.2 APIs for creating and navigating browsing contexts by name
      2. 5.2.3 Accessing other browsing contexts
      3. 5.2.4 Named access on the Window object
      4. 5.2.6 Browser interface elements
    3. 5.3 Origin
      1. 5.3.1 Relaxing the same-origin restriction
    4. 5.4 Session history and navigation
      1. 5.4.1 The session history of browsing contexts
      2. 5.4.2 The History interface
      3. 5.4.3 The Location interface
    5. 5.5 Browsing the Web
      1. 5.5.9 History traversal
      2. 5.5.10 Unloading documents
    6. 5.6 Offline Web applications
      1. 5.6.1 Introduction
        1. 5.6.1.1 Event summary
      2. 5.6.3 The cache manifest syntax
        1. 5.6.3.1 Some sample manifests
        2. 5.6.3.2 Writing cache manifests
      3. 5.6.9 Application cache API
      4. 5.6.10 Browser state
  6. 6 Web application APIs
    1. 6.1 Scripting
      1. 6.1.1 Introduction
      2. 6.1.6 Events
    2. 6.2 Base64 utility methods
    3. 6.3 Timers
    4. 6.4 User prompts
      1. 6.4.1 Simple dialogs
      2. 6.4.2 Printing
      3. 6.4.3 Dialogs implemented using separate documents
    5. 6.5 System state and capabilities: the Navigator object
      1. 6.5.1 Client identification
      2. 6.5.2 Custom scheme and content handlers
      3. 6.5.3 Manually releasing the storage mutex
  7. 7 User interaction
    1. 7.1 The hidden attribute
    2. 7.2 Activation
    3. 7.3 Focus
      1. 7.3.1 Sequential focus navigation and the tabindex attribute
      2. 7.3.3 Document-level focus APIs
      3. 7.3.4 Element-level focus APIs
    4. 7.4 Assigning keyboard shortcuts
      1. 7.4.1 Introduction
      2. 7.4.2 The accesskey attribute
    5. 7.5 The contenteditable attribute
      1. 7.5.2 Making entire documents editable
    6. 7.6 Spelling and grammar checking
    7. 7.7 Drag and drop
      1. 7.7.1 Introduction
      2. 7.7.2 The drag data store
      3. 7.7.3 The DataTransfer interface
        1. 7.7.3.1 The DataTransferItems interface
        2. 7.7.3.2 The DataTransferItem interface
      4. 7.7.4 The DragEvent interface
      5. 7.7.6 Events summary
      6. 7.7.7 The draggable attribute
      7. 7.7.8 The dropzone attribute
    8. 7.8 Editing APIs
  8. 8 The HTML syntax
    1. 8.1 Writing HTML documents
      1. 8.1.1 The DOCTYPE
      2. 8.1.2 Elements
        1. 8.1.2.1 Start tags
        2. 8.1.2.2 End tags
        3. 8.1.2.3 Attributes
        4. 8.1.2.4 Optional tags
        5. 8.1.2.5 Restrictions on content models
        6. 8.1.2.6 Restrictions on the contents of raw text and RCDATA elements
      3. 8.1.3 Text
        1. 8.1.3.1 Newlines
      4. 8.1.4 Character references
      5. 8.1.5 CDATA sections
      6. 8.1.6 Comments
    2. 8.5 Named character references
  9. 9 The XHTML syntax
  10. 11 Obsolete features
    1. 11.1 Obsolete but conforming features
    2. 11.2 Non-conforming features
  11. 12 IANA considerations
    1. 12.1 text/html
    2. 12.2 text/html-sandboxed
    3. 12.3 application/xhtml+xml
    4. 12.4 text/cache-manifest
  12. Index
    1. Elements
    2. Element content categories
    3. Attributes
    4. Interfaces
    5. Events
  13. Index of terms
  14. References
  15. Acknowledgements