Audience - it is all about the audience.

This chapter turns to a consideration of the audience during a presentation and make an impact on them. Presenters always address a specific audience, in a specific venue, on a specific topic. The most important thing to consider when planning a presentation is the audience. The audience will determine how much technical language one can use, how much background information one must present, and even what clothes one wears. Failure to take this into account is one of the problems with many scientific presentations.