Well, article marketing is necessary for your online business. Article marketing is not just writing article but also marketing them as the name suggests.
Article marketing can help you boost you increase your sales and its free too unlike advertising.
By submitting your articles to different article directories, e-zine publishers you achive a lot of invaluable things.
First of all, you master the art of writing in the web and become a expert at your field. If readers know what you are writing about then they are more likely to read your next post.
Second, By attaching a resource box at the bottom of your article you are giving the reader a link to your website. If you have impressed your reader enough by your article then they are certainly going to visit your website.
Third, this is definitely going to increase the SEO of your website because of the non-reciprocal link to your website. This will increase your SEO and will end up giving you a bunch of visitors.
Just consider the case if you were not doing article marketing you would lose all the three invaluable advantages and your sales would be under average as a result.