Visitor vs. Registered vs. Anonymous users

[azism]

What is the difference between a visitor and and an anonymous user?  

Unless I set the album permissions to Visitor Can Upload, a registered user can't upload. But with that setting, can an anonymous user also upload??? I only want registered users to be able to upload. It is the designation of "Visitor" that has me confused. Could someone please clarify this for me? Thanks in advance!  

[hyperion]

Im the current version, album permissions are controlled in two locations. The visitor designation means anyone who visits the album regardless of the user group. You then go to the groups console, whereyou designate the permissions for each group, such as 'can upload', etc.