Here's a breakdown of our current user roles:

Administrator – Access to all the administration features within your site (like billing) and all design features. Full access to everything.

Editor – Access to everything except billing and adding/deleting users.

Author – Access to publish, edit, or delete their own blogs, podcasts, events, groups, announcements and forms, but they can’t access anything created by other users and they can’t create, edit, or delete pages.

Contributor – Access to write, edit, and delete their own unpublished posts (blogs, podcasts, events, groups, announcements and forms), but their content must be reviewed and published by an Admin or Editor. Contributors can’t access the Media Library, so if they want to use specific images, videos, or audio files in the Media Library, they have to ask for assistance from an Admin or Editor.

Subscriber – Actually doesn't do anything and is just there for legacy purposes. Ignore it.