The pressing of Puerh tea into cakes and the aging of the tea perhaps originated in the need to transport the tea conveniently from Yunnan to Tibet and northern China and in the natural aging process that happened in tea storerooms and during transport.
While Puerh Tea is predominantly pressed into cakes, an interesting variety of additional compact shaped may be used including squares, bricks, bowls, mushrooms, and melons. Most Puerh Tea is distributed in small cakes weighing about 357 grams. Regardless of the final shape, each of these forms is created by steam-moistening the máochá or ripened tea leaves to improve cohesion prior to compressing the tea into the desired form. Occasionally, cakes are made of older leaves mixed with the current year leaves. This mixing is, unfortunately, difficult to get information about as it is considered a trade secret.
Next, the desired amount of tea is placed within a cloth and under the press. This compression can be preformed mechanically or by hand with a hydraulic or lever press. Traditionally, a large rock was used for the pressing. A small piece of paper called a Nèi fēi will also be pressed in with the tea, as a sign of authenticity that resists easy tampering. The pressed tea must be allowed to dry prior to packaging and sale.
When sold individually, each pressed cake will come in a cotton wrapper printed with information on the production location and year of production. These wrappers also sometimes include interesting artwork. As mentioned above, the cake will have an impressed authenticity paper embedded in the tea with manufacturer information. Some cakes will also include a loose flyer with additional information about the tea. Pu-erh is also sold wholesale in larger bamboo containers called tong.

Puerh is an aged tea from China that is fermented and matured to develop a unique mellow, slightly wet earthy character. The finest puerhs are aged for up to 50 years and become more mellow and soft over time. In China, this category of tea is considered to be a medicinal beverage that helps metabolize fats. It is ideal for digestion and is said to help prevent hangovers.