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A threadcast is a live chat (eg. Lion's Den, AMA, sport event, whatever).

A container is a thread on a particular topic with a bunch of related threads in replies (not a live chat).

Thanks for the clarification, @adambarratt!

I should say, that tagging #threadcast in a top level thread generates the live chat environment, which is what differentiates it from other tags

Okay, thanks again.

Okay. It's making more sense now. Thanks again!