There are four levels of increasing security: View Only,
Add Events, Edit Events, and Administer.
Higher levels include permission for all lower ones, so anyone
with Edit permission can also View and Add events, while those
with Administer permission can do anything. Note that any
user with System Administration
Permission will always have Administer permission in any
The "Effective Permission" shows each user's highest access,
based on the Default Security level, all the User Groups
they are a member of, as well as User Group permissions
assigned to Calendar Groups.