Article spinning works by rewriting existing articles, or parts of articles, and replacing specific words, phrases, sentences, or even entire paragraphs with any number of alternate versions to provide a slightly different variation with each spin. This process can be completely automated or rewritten manually. Many article marketers believe that article spinning helps avoid the feared penalties in the Search Engine Results Pages (SERP) for using duplicate content.
The purpose of article spinning is to generate filler content for a site, similar to scraper sites, which directly rip segments of content away from various sites to make up itself. Sites that have spun content on them most likely have no other content to offer aside from advertisements.