What are 'Attachments' for in a Zoho Desk ticket?

What are 'Attachments' for in a Zoho Desk ticket?

* When a new ticket with attachments is created, the attachments stay in the email thread. 
* If we add documents to the 'Attachment' section of the ticket, They do not show available when trying to attach to an email. 

1. What would I use 'Attachment' tab for?
2. Is there a Custom Function that would automatically put all attachments from any email into the 'Attachment' tab of the ticket?

thanks