Wanchojang refers to a craftsman who has three levels of functions: the function of screening and processing after cultivation of a complete plant, the function of dyeing the plant with paint, and the function of reviving aesthetic elements with proper arrangement of dyeing finished plants.

It was recorded that the Wancho craft was used in the "Samguk Sagi" from Silla. During the Joseon Dynasty, the government office included Wanggol as one of the items that required public payment, indicating that Wancho crafts were very valuable.

Han Myeong-ja, a master of the Wanchojang, produces works with everyday artifacts that combine beauty and use, such as granite, bowl form, and octagonal box, and is also making utmost efforts to transfer the function of Wancho Craft.

Wanchojang refers to an artisan with the skill of making objects with sedge (Cyperus exaltatus, wanggol in Korean), which is an annual/biennial plant that grows in a wet rice paddy or swamp. It grows to a height of 60 – 200cm. Sedge is used to make mats, seat cushions, and baskets.

According to Samguk sagi (History of the Three Kingdoms), sedge was used during the Silla Period (circa 57 BC – 935 AD). During the Goryeo Period (877 – 1394), a sedge mat was laid on the place where the deities of the State are enshrined. Sedge mats were used chiefly in royal palaces, and they were also sent to China as gifts. During the Joseon Period (1392 – 1910), sedge mats were used mostly in royal palaces or in the homes of upper class people. In foreign trade, the mats made in Korea were regarded as luxury goods.

Sedge products are made either manually or with tools. Mats and cushions are made either with a coarse weaving technique with warps exposed or with a close weaving technique with warps not exposed. As for the manual weaving method, eight warps are entwined to form a “井” shape and then two wefts are woven into it to make round or octagonal cushions and baskets.

Production of sedge goods once went through the doldrums, but it regained strength in the 1970s and thereafter. Up to now, sedge has been used chiefly to make mats and baskets, but it can be used to make many other objects without the need for special tools by adjusting the colors and the thickness of warps and wefts.