History
The history subfolder holds all of the originating emails and subsequent replies from the caller. When you open a support case, there is a tab 'Email History' and it lists all the replies in chronological order that were received from that caller. Every help desk staff would require to have editor permission over this folder to work with support cases.

The History folder includes a custom SupportCalls view (as shown below) that group email replies from caller based on case number.