An historical account of the use of parchment in the history of the transmission of the New Testament is given by Dr. Daniel B. Wallace of the Center for the Study of New Testament Manuscripts (CSNTM).  In this video, Dr. Wallace surveys the reasons for the use of parchment instead of papyri and the methods by which parchment came to be from animal skins.  Dr. Wallace also discusses interesting uses of parchment that rendered the creation of palimpsests of which a famous manuscript known as Codex Ephraemi Rescriptus belongs.