What is backchanneling?

Backchanneling is the use of a live network to have an online conversation while a presentation is going on. As presenters sometimes we wonder, "What is the audience really thinking?" "Do they have questions that I am not answering." While the audience might be thinking, "What did they just say?" "I don't get that, what about this theory." Well, the backchannel is where the audience can actually post these thoughts without distracting the presenter or those around them. The presenter is also able to know immediately if the goal of the presentation is being met. So as teacher's how can we use this in the classroom? I think ultimately it can increase engagement in what might normally be passive activities in the classroom. Some interesting reading regarding this concept: http://www.ncs-tech.org/?p=2886 "What is backchanneling and how can you use it in your classroom?"