In dust.js, what is a streaming interface?

I used dust.js with a callback interface, and it is very convenient for me. Now I want to know more about the streaming interface.

I have been over the documents here and here and the concept runs away from me.

I think my question is:

• What does a streaming template mean? It seems to me that I can use it to install an object that, when clicked on, will respond to the rendering of this data according to the template.

• In what cases would I use Streaming instead of the Callback Interface?

• Are there any code examples that can help me find out?

Thank!