HTML: The Markup Language

2. Terminology # T

The following is a list of terms that are used in other sections of this reference.

browsing context
An environment in which UAs present documents to users. A tab or window in a Web browser typically contains a browsing context, as does an iframe, or frame elements in a frameset.
case-insensitive match
An exact comparison of two strings, codepoint for codepoint, except that the characters in the range A-Z and the corresponding characters in the range a-z are considered to also match.
DOM tree
A representation of a document based on the W3C Document Object Model (DOM), as defined in the [DOM4] specification. UAs build representations of documents by parsing them and constructing DOM trees from them.
fallback content
Content associated with embedded content, to be used when the embedded content cannot itself be used (for example, when the embedded content is of an unsupported format).
flow content
Flow content consists of flow elements intermixed with normal character data.
HTML producers
HTML authors (that is, people) and applications (such as editors and content management systems) that produce HTML content.
HTML consumers
HTML user agents; that is, applications (such as Web browsers) which consume HTML content.
The word must is used in this reference to mark document-conformance requirements that are normatively defined in the HTML5: A vocabulary and associated APIs for HTML and XHTML full specification. [HTML5].

This reference does not itself normatively define any requirements.

Any of the following:
  • a U+000D CARRIAGE RETURN (CR) character
  • a U+000A LINE FEED (LF) character
  • a U+000D CARRIAGE RETURN (CR) followed by a U+000A LINE FEED (LF) character
phrasing content
Consists of phrasing elements intermixed with normal character data.
resolve a URL
To resolve a URL to an absolute URL, as defined in [HTML5].
Any of the following:
  • U+0020 SPACE
  • U+000A LINE FEED (LF)
  • U+000C FORM FEED (FF)
top-level browsing context
As defined in [HTML5].
If the content model of a particular element foo is described as transparent, it means:
  • when element foo is a child of a parent element bar whose content model is allowed to contain flow elements, then the contents of element foo may also contain flow elements
  • when element foo is a child of a parent element baz whose content model restricts its child elements to only being phrasing elements, then any child elements of element foo are also restricted to only being phrasing elements
An HTML user agent; that is, an application (such as a Web browser) which consumes HTML content.