Black hat SEO attempts to improve rankings in ways that are disapproved of by the search engines, or involve deception. One black hat technique uses hidden text, either as text colored similar to the background, in an invisible div, or positioned off screen. Another method gives a different page depending on whether the page is being requested by a human visitor or a search engine, a technique known as cloaking. Another category sometimes used is grey hat SEO. This is in between black hat and white hat approaches, where the methods employed avoid the site being penalized but do not act in producing the best content for users. Grey hat SEO is entirely focused on improving search engine rankings.
I completely agree that defintion of a target audience isa great first step, but would ask if adding in competitors to the analysis (mentioned here as a later step) helps draw out who your target audience would be via comparisons, i.e. showing who you are an who you are not - would be very interested to hear opinions on how this tactic can be used within the overall step in coordination with targeted keyword discovery.