An article directory is a web site maintained to house articles written by individuals who want to spread their fame on the internet. When these authors place their articles in the directory, they are giving permission to all the visitors to the directory to read the article there, but, more importantly, to reprint the article on any website they own.
Each article in the directory has an information paragraph about the author. This author information must be included with the article when it is reprinted. This information usually contains a link to the author's website (so that readers can easily visit) and other business information about the author.
The attraction of these article directories for authors is that their article may be reprinted by various webmasters and each time it is reprinted another link to the author's site is created, as well as another mention of the author's name, both of which can bring additional prominence to the author and additional traffic to the author's site.
Article Marketing is the process of creating articles (usually of length 300-1000 words) and placing them online in article directories (q.v.) in hope that these articles will increase the reputation of the author.
Once highly touted as a marketing tool, article marketing is being used less frequently, due to the difficulty and time involved in writing a good article. Even so, it still has proponents.