Search Engine Optimization is the designing of your article with the most searched keywords about a particular topic. The using of these keywords can convince the search engines like Google that the article or site has substantial information regarding the topic thereby creating more traffic to the website.
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If you write articles with proper syntax (select appropriate heading, Use good Keywords, use html tags effectively and arrange articles properly) then your article have good search engine optimization. That means your article will have good traffic and that will benefit you. To know more about SEO go through following links.