Anonymous is a term used in Drupal to refer to users who are not logged in to the system. Anonymous users are not identified by the system and do not have any associated user account. They are typically identified by their IP address, which is used to track their activity on the site. Anonymous users are usually given limited access to the site, such as viewing content but not being able to comment or post content.
In Drupal, anonymous users are given a special role called "anonymous user". This role is used to control what anonymous users can do on the site. For example, the anonymous user role can be used to restrict access to certain content or features, or to limit the number of comments a user can post. It can also be used to control what anonymous users can see when they visit the site.
Anonymous users are an important part of any Drupal site, as they provide a way for people to view content without having to create an account. This allows people to quickly and easily access content without having to go through the process of creating an account. It also allows the site to track anonymous user activity, which can be used to improve the user experience.