Before contributing, authors must gain permission to add content. While by design or defect some locations do not restrict contribution, most intelligence collects from credentialed authors. In other words, authors must be registered participants with validated access. In the Drupal environment, registered participants are users; a validated access is called a session.

To become a user, visitors to a Drupal site must register a user name. Most Drupal sites require a valid e-mail address. Validation does happen by various means, but most often a password is associated with each site user. Users get a session after authenticating on a site login form. Access is facilitated by a "User login" block on default Drupal sites. Some Drupal site administrators will add a menu item for "User login" with labels that could be useful hints. Most Drupal sites allow contribution, of some flavor, from any authenticated user.

Contributions come in many flavors. One basic, default content of a Drupal site is a "story" — consisting of a title and body. A second, default content type is a page — also consisting of a title and body. Drupal stories and pages may be contributed with no more than typing and mouse skills.

The default Drupal site offers a "Create content" link to session users in the navigation menu. When a user clicks on that link, a page opens with descriptions of all content types for which that user has authorization. The name at the beginning of each description is a link to that specialized contribution's submission form. Options, allowed for the content type, are adjusted in the submission form.

By default, Drupal sites accept filtered HTML for content. This means

• Web page addresses and e-mail addresses turn into links automatically.
• Allowed HTML tags: <a> <em> <strong> <cite> <code> <ul> <ol> <li> <dl> <dt> <dd>
• Lines and paragraphs break automatically.

For the uninitiated web content author, the list of allowed HTML tags are meaningless — and unnecessary for adding content into a Drupal site. Just type like you would when writing a normal letter to a friend and Drupal will take care of the layout (another meaningless term for the uninitiated). For the experienced web content author, some sites allow additional HTML tags when using the "Full HTML" input format. Non-administrative contributors should not use nor even find the "PHP code" filter — this advanced format is not allowed by most responsible administrators and needs no discussion here.

Other content types may be added to suit specialized interests. Images may be a content type — other content types may be audio samples, polls, order forms, blog entry, forum content, organic group, organic group content, etc … . There are growing numbers of content types, developed for specialized collections and, if what's already available is not adequate, special content can be designed with the "content construction kit (or CCK).