SEO content is specially optimized to be picked up by the search engines through the strategic inclusion of keyword phrases. Ensuring that these keywords are spread out throughout the document helps to ensure articles are indexed by the search engines, helping to boost your search rankings and increase web traffic.
In the early days of SEO, Google and other search engines tended to rank websites according to the quantity of keywords in the content, rather than the quality of the content itself. This resulted in reams of awkward articles that were literally stuffed with keywords, able to game the search engines but unable to offer much actual value to human readers.
Within the past few years, search engines have completely changed their algorithms and now penalize websites that do this. With this in mind, we recommend that SEO content contains two to four keyword phrases, each included two to three times per 500 words.