According to Price and Price, audiences were traditionally thought of as a vast and vaguely defined crowd (Price & Price, 2002). Because the web provides a voice to individuals and niche groups, the concept of this mass audience is disintegrating.
Price and Price go on to argue that the Internet has led to an audience of one (Price & Price, 2002). What does this mean? While your audience is not literally one person (and if it is, thank your mum for reading your copy, but spend some time growing your readership), it is not a vast, vaguely defined crowd either. Instead, the web has many niche audiences who are used to being addressed as individuals.
When you are writing marketing material, you need to identify that ‘individual’, investigate what he or she wants, and write as if you are speaking directly to him or her. The individual that you have in mind when you are writing could also be called a persona.
