The term "Jōmon" (縄文) means "rope-patterned" in Japanese, describing the patterns that are pressed into the clay.
[1] Odai Yamamoto I site in Aomori Prefecture currently has the oldest pottery in Japan.
Excavations in 1998 uncovered forty-six earthenware fragments which have been dated as early as 14,500 BCE (ca 16,500 BP); this places them among the earliest pottery currently known.
Both linear-relief, and 'nail-impressed' pottery were found at Torihama shell mound, in Fukui prefecture, dating to 12000-11000 BC.
This refers to the impressions on the surface of the pottery which were created by pressing rope into the clay before it was heated to approximately 600–900 degrees Celsius.