Subscriber
The Subscriber role is set by default for new registrations on WordPress websites. This role is limited to reading content but not much else. If comments are active, the subscriber can leave a message. Otherwise, he or she is unable to submit or publish any content on the system.
Contributor
Contributors can submit, edit and delete their own articles that are unpublished. However, the ability to publish a post is not available. These people are only able to save content as drafts.
Author
An author has a bit more control than a contributor. This person is capable of publishing his or her own posts as well as edit and delete. However, the author is incapable of interacting with the work of someone else.

