"Original Documents" is the blanket term used to describe the master copy of legal papers. Most documents you receive are simply a scan, photocopy, or printout of the pages that were filed at court. Original Documents are unique in that they are the very same pages that have been handled since the beginning of the court proceedings. Depending on the case, you may be the recipient of Original Documents - Child Support cases, Subpoenas, and International Services are a few types of Original Documents you could be asked to serve.
Original Documents will always be delivered to your mailbox. Since there is only one master copy, they cannot be printed out. Most Original Documents you receive will have a colored coversheet, and all will be marked with an insignia saying "Return Original Documents." This insignia is your best indicator that you are in possession of originals.
Serve them! They should be served just like any other job you receive. Pay close attention to the special handling instructions, as originals often have requirements to be aware of. There are a few key differences to note, however: