What are Articles?
You can think of an article as a page on your site. We prefer the term article, rather than page, because you're in the business of publishing content. You might not have thought of yourself as a publisher before, but when you write something for a website, you're journalist, author and publisher all rolled into one.
It's also important to remember that not all articles will be pages. Some articles are used to create menus, some are purely "system" articles, and some provide snippets of content that form part of other articles.
What about Templates?
Each article you publish will use a template. The template will control what your article looks like and the additional content it displays.
Most articles you create will use the Default template, which simply publishes the content in the way you tell it to. Other templates include the Forms Service template (for displaying forms), the List template (for displaying a list of other articles) and the Search template (which automatically includes a search box). There's a lot more information in the Templates documentation.
The ability to create and edit articles is controlled by a user's iCM Privileges.