There are notes for ¥100, ¥50, ¥20, ¥10, ¥5, ¥2, and ¥1, which also appears as a coin. The word yuan is rarely spoken, and sums are usually referred to as kuai qian, “pieces of money,” usually shortened to just kuai. San kuai is ¥3. The next unit down, the jiao (¥.10), is spoken of as the mao. There are notes of a smaller size for ¥.50, ¥.20, and ¥.10, as well as coins for these values. The smallest and almost worthless unit is the fen (both written and spoken) or cent and, unbelievably, when you change money you may be given tiny notes or lightweight coins for ¥.05, ¥.02, and ¥.01, but this is the only time you’ll see them except in the bowls of beggars or donation boxes in temples. The most useful note is the ¥10, so keep a good stock. Street stalls, convenience stores, and taxis are often not happy with ¥100 notes.
Keep receipts when you exchange money, and you can reconvert excess yuan into hard currency when you leave China, although sometimes not more than half the total sum for which you can produce receipts, and sometimes these receipts must be not more than 3 months old.