So you submit them into directories, and the directory PAGES containing my content is displayed on the search engines?
It acts like a website page?
Yes this is a web page that the search engines will crawl and index. When optimizing your articles you will want a keyword relevant page title (some directories will not let you control this), the article title with relevant keywords in it as well as the content of the article itself. Any time you link to the site you are trying to promote, use keyword text as the link refer instead of the site name. So if you are trying to promote blue widgets for widgets.com you would use a link of "lowest priced blue widgets" instead of just "widgets.com". This way the link uses keywords that point back to your website. The search engines love these types of links pointing back to your site instead of just the site name. Other then that do not stuff your article full of keywords or trying and optimize it for 15 different keyword phrases as it probably will not sound right and look spammy to the search engines.