User permissions allow you to control what users have access to on your site. For example, you can allow anonymous users on your site to see content but only allow authenticated users to post comments. To view your user permissions go to:

Administration menu » User management » Permissions

Depending on the functionality of your drupal site the amount of permissions that can be set could be vast. You will want to carefully go through this page to determine which user roles should have access to which parts of your web site.

Permissions on other parts of your site

There are many other parts of your web site where permissions can be used or content can be created what will add more permission options to the permissions page. The following are the most common examples:

Content types

Each content type that you create will create additional permissions that can be used. This allows you to create content types that only the roles with the correct permissions will be able to view/edit/create/delete. This can be very useful on sites where you would like to provide payed content or content that you would only like to be available to registered users.

Blocks

Each block allows you to define which roles can see it. If you don't select any specific roles it will show for all roles but if you only check "anonymous user" for example only users that are not logged on will see that block.