This document specifies the third version of the Synchronized Multimedia Integration Language (SMIL, pronounced "smile"). SMIL 3.0 has the following design goals:

• Define an XML-based language that allows authors to write interactive multimedia presentations. Using SMIL, an author may describe the temporal behaviour of a multimedia presentation, associate hyperlinks with media objects and describe the layout of the presentation on a screen.
• Allow reusing of SMIL syntax and semantics in other XML-based languages, in particular those who need to represent timing and synchronization. For example, SMIL components are used for integrating timing into XHTML [XHTML10] and into SVG [SVG].
• Extend the functionalities contained in the SMIL 2.1 [SMIL21] into new or revised SMIL 3.0 modules.
• Define new SMIL 3.0 Profiles incorporating features useful within the industry.

This document specifies the second version of the Synchronized Multimedia Integration Language (SMIL, pronounced "smile"). SMIL 2.1 has the following design goals:

• Define an XML-based language that allows authors to write interactive multimedia presentations. Using SMIL, an author can describe the temporal behaviour of a multimedia presentation, associate hyperlinks with media objects and describe the layout of the presentation on a screen.
• Allow reusing of SMIL syntax and semantics in other XML-based languages, in particular those who need to represent timing and synchronization. For example, SMIL components are used for integrating timing into XHTML [XHTML10] and into SVG [SVG].
• Extend the functionalities contained in the SMIL 2.0 [SMIL20] into new or revised SMIL 2.1 modules.
• Define new SMIL 2.1 Mobile Profiles incorporating features useful within the mobile industry.

This is a W3C Recommendation of a specification of animation functionality for XML documents.  It describes an animation framework as well as a set of base XML animation elements suitable for integration with XML documents. It is based upon the SMIL 1.0 timing model, with some extensions, and is a true subset of SMIL 2.0. This provides an intermediate stepping stone in terms of implementation complexity, for applications that wish to have SMIL-compatible animation but do not need or want time containers.

This specification defines an XML timing language that makes SMIL 3.0 element and attribute timing control available to a wide range of other XML languages. This language allows SMIL timing to be integrated into a wide variety of a-temporal languages, even when several such languages are combined in a compound document. Because of its similarity with external style and positioning descriptions in the Cascading Style Sheet (CSS) language, this functionality has been termed SMIL Timesheets.

This document specifies usage scenarios and requirements for a timed text authoring format. A timed text authoring format is a content type that represents timed text media for the purpose of interchange among authoring systems. Timed text is textual information that is intrinsically or extrinsically associated with timing information.

The XHTML+SMIL profile defines a set of XHTML abstract modules that support a subset of the SMIL 2.0 specification.

This document specifies the distribution format exchange profile (DFXP) of the timed text authoring format (TT AF) in terms of a vocabulary and semantics thereof.

The timed text authoring format is a content type that represents timed text media for the purpose of interchange among authoring systems. Timed text is textual information that is intrinsically or extrinsically associated with timing information.

The Distribution Format Exchange Profile is intended to be used for the purpose of transcoding or exchanging timed text information among legacy distribution content formats presently in use for subtitling and captioning functions.

In addition to being used for interchange among legacy distribution content formats, DFXP content may be used directly as a distribution format, for example, providing a standard content format to reference from a <text> or <textstream> media object element in a [SMIL 2.1] document.