Any definition of internet marketing needs to come along with a definition of things associated with it such as affiliate marketing, network marketing, multi-level marketing and so on and so forth. Some of these are less legitimate than others. For example, affiliate marketing is a tough nut to crack unless you have a massive following or you understand how to build excellent squeeze pages and effective sales funnels.
SEO techniques can be classified into two broad categories: techniques that search engine companies recommend as part of good design ("white hat"), and those techniques of which search engines do not approve ("black hat"). The search engines attempt to minimize the effect of the latter, among them spamdexing. Industry commentators have classified these methods, and the practitioners who employ them, as either white hat SEO, or black hat SEO. White hats tend to produce results that last a long time, whereas black hats anticipate that their sites may eventually be banned either temporarily or permanently once the search engines discover what they are doing.