The Web is a natural platform for multimedia, with universal reach, powerful
backend services and a rich selection of components for capture, interactivity
and presentation. In addition, with a strong commitment to modularity,
composition and interoperability, the Web should allow advanced media
experiences to be constructed by harnessing the combined power of simpler
components. Unfortunately, with timed media this may be complicated, as media
components require synchronization to provide a consistent experience. This is
particularly the case for distributed media experiences.

In this chapter we focus on temporal interoperability on the Web, how to allow
heterogeneous media components to operate consistently together, synchronized
to a common timeline and subject to shared media control. A programming model
based on external timing is presented, enabling modularity, interoperability
and precise timing among media components, in single-device as well as multi-device 
media experiences. The model has been proposed within the W3C Multi-device 
Timing Community Group as a new standard, and this could establish
temporal interoperability as one of the foundations of the Web platform.
