Replies are written in a rich-text editor that supports formatting, inline images, and file attachments. If you find yourself typing the same answer often, save it as a canned response and insert it into future replies in a click, then personalize it before sending.
You can CC or BCC additional people on a reply so they stay informed without being the primary requester, and you can add internal notes that are visible to your team but never sent to the customer - useful for leaving context for whoever picks up the ticket next.