SMIL (pronounced "smile") is an abbreviation for the Synchronized Multimedia Integration Language.
It is a W3C Recommendation for describing multimedia presentations
using XML (Extensible Markup Language). It defines timing markup,
layout markup, animations, visual transitions, and media embedding,
among other things.
SMIL 1.0 became an official recommendation of
the World Wide Web Consortium W3C in June 1998. SMIL 2.0 became an
official recommendation in August 2001. SMIL 2.1 became an official
recommendation in December 2005. SMIL 2.1 includes a small number of
extensions based on practical experience gathered using SMIL in the
Multimedia Messaging System on mobile phones.
A SMIL document is similar in structure to an HTML
document in that they are typically divided between a <head>
section and a <body> section. The <head> section contains
layout and metadata information. The <body> section contains the
timing information, and is generally comprised of combinations of two
main tags: parallel ("<par>") and sequential ("<seq>").
SMIL refers to media objects by URLs, allowing them to be shared
between presentations and stored on different servers for load
balancing. The language can also associate different media objects with
different bandwidths.
