When you join a meeting, your default role is participant. As a participant, you can view information shared by a presenter, view video and meeting notes, and chat with other attendees.
If you are a presenter in a meeting, you can share your screen, type in the Note pod, change pod settings, and maximize and restore various pods in order to facilitate your presentation. Only the meeting host can promote a participant to the presenter role. The host can change the role of an individual participant, or may choose to have all attendees enter the meeting as presenters instead of participants.