Affiliate marketing is the art of marketing products, services or information for others. It doesn't require that you ever house or warehouse a single thing. But it does require that you have an audience to market those things to online. Without that audience, whether it's through search engines like Google or social media channels like Facebook, you'll find a difficult time with affiliate marketing.
Social marketing is sometimes seen as being restricted to a client base of non-profit organizations, health services groups, the government agency. However, the goal of inducing social change is not restricted to this narrow spectrum of organizations. Corporations, for example, can be clients. Public relations or social responsibility departments may champion social causes such funding for the arts, which would involve social marketing.
Affiliate marketing overlaps with other Internet marketing methods to some degree, because affiliates often use regular advertising methods. Those methods include organic search engine optimization (SEO), paid search engine marketing (PPC – Pay Per Click), e-mail marketing, content marketing, and (in some sense) display advertising. On the other hand, affiliates sometimes use less orthodox techniques, such as publishing reviews of products or services offered by a partner.