Let’s start by thinking about the purpose of asking questions at a scientific presentation. Obviously, we ask questions when we didn’t understood something. If someone didn’t understand a part of a presentation, most likely some other people in the audience didn’t either. Questions are thus asked to help the comprehension of the entire audience. Scientists also ask questions even when they are not expecting any answers. Such “questions” are often advice for the presenter, a suggestion of an alternative hypothesis, or a problem raised to the entire audience. In other words, questions and answers serve to deepen the understanding of all members of the audience, and to encourage the exchange of ideas among everyone at the venue. No scientific presentation is complete without an active Q&A session.