Are you questioning as same as me, what is an online presentation or how to do online presentation? 
An online presentation is a type of content that brings the traditional classroom presentation into a video presentation.  It is typically using Microsoft PowerPoint (PPT) to an anytime, anywhere environment online either personal web, YouTube or school website.  Through iEARN online presentations can take several different formats.  In many online presentations, slides are just the base.  The presenter of iEARN projects can add pictures, charts, video feeds into a single interactive presentation viewer.

But how to do online presentation?
I love my students to do PPT presentation including short videos, pictures and charts. You can show it through online, narrated in audio, you can also interact with the audience through your video. 

No matter what type of presentation are you doing, there are strengths and benefits thorough online. Therefore, every presentation should be part of a content that students can create their own learning portfolio.  The difference among "Online" presentation and "Live" presentation is in the richness of the media experience, the level of interactivity offered to the viewer, and the trackability and value of the data that’s generated every time a viewer interacts with the material.

Even the video can stay on the website or on the YouTube forever. However, I prefer "Live" presentation.

Why is live presentation better?

A live presentation helps to share iEARN projects with other schools. Through live presentation, students are contributing language and their learning experience.

In other words, they will able to put more efforts on enunciation, team work and they will understand the importance of presentation skills and how to connect with their audience.