SMIL file takes the place of a RealSystem
.ram file and has three main purposes:
It describes the overall layout of the presentation.
It serves as the macro metafile for the presentation, sourcing media and data files, as well as other, more specific metafiles.
It establishes the overall presentation timeline.
Because each element in a SMIL-based presentation can be encoded and transmitted separately with synchronization control, content creators can optimize their presentations by choosing the least bandwidth-intensive format necessary to transmit data. This reduces the bandwidth required to stream the whole package and makes it easier to edit the presentation later.
A powerful advantage to encoding pieces of the presentation in separate files and using SMIL to control their interaction is the increased ease and flexibility over editing presentations encoded together in a single file. For example, if you decide after finishing the presentation that you would like the audio portion of a presentation to begin five seconds after the rest of the presentation begins, you can use SMIL to set a start time for the audio track at five seconds, without having to edit the audio file itself.
In general, SMIL is a tag-based markup language similar to HTML. A few basic syntax rules to remember in SMIL are: ...