The chaou is a three piece teaware consisting of a lid, cup/bowl, and a saucer. Chaous are generally made of porcelain or are glazed on the inside in order to prevent a buildup of tannins. The chaou may be used on its own or with tasting cups on the side. Chaou brewing is usually employed in tea tasting situations, such as when buying tea, where neutrality in taste and ease of access to brewing leaves for viewing and sniffing is important. This method of serving is often used in informal situations, though it can also be used on more formal occasions. Chaou brewing can be used for all forms of teas though lightly oxidized teas benefit most from this brewing method.