Briefly, prewriting is the first stage of the writing process, which includes all the effort and activities to prepare for writing your first draft. The more you do, the easier the rest of the writing process will be - believe me, this stuff really works. This discussion concerns prewriting for nonfiction writing projects, especially books and larger projects, but it is also applicable for shorter e-books and projects.
Here are some of the major activities associated with prewriting:
It allows you to determine whether the project idea is actually a book, an article, or just a blog post. And you can decide the type of project it will be: a book, workbook, course, or whatever will best meet the needs of your readers.
It helps you select a project idea if you have several to choose from.
It helps you explore your vision for the writing project, including the benefits you hope to gain as the writer and the benefits you hope to provide to your readers.
It encourages you to define and characterize your audience, so you can fulfill their needs with your writing.
It allows you to dig more deeply into your topic by defining the problem that you are writing about, listing the solutions you will offer, and filling in the gaps with research.
It asks you to analyze your competition and their offerings, so that you can see how your ideas about the topic fit into the content already on the market. Are your ideas unique, or are they simply a rehash of information already written about the topic?
It allows you to decide the types of information and the methods used to convey this information in the project.
Prewriting ends with your creation of an Extended Outline (my term), which you then use as a writing guide for writing your first draft.
So, there is a brief list of the most important aspects of prewriting. Sure, much effort and activity is involved in prewriting, but if you do it right and completely, the rest of the writing process will be much easier than if you just start writing with your first draft, with only minimal thought about the project.
And you are much more likely to finish the project if you do the prewriting because you have thought out the project in detail and know your content and intentions. And you know your writing project will be of great use to your readers.
In addition, I use several effective techniques in my own prewriting activities, such as the Expanded Brainstorming Questions technique, and the Development Methods as Idea Generators technique, among others.