Chinese cinnamon is the inner bark of the Cinnamomum Cassia tree. Cinnamon contains coumarin, a substance that may damage your liver in high doses. The coumarin content of Ceylon cinnamon is far lower than that of Chinese cinnamon - so if you plan on using major amounts of cinnamon, you may want to choose the Ceylon cultivar.
Chinese cinnamon has a mild and slightly nutty taste compared to Ceylon cinnamon, and it is excellent for Moroccan and Middle East spice mixes that require a twinge of cinnamon that does not drown out other ingredients.
In Western countries, cinnamon is primarily used to add flavour to desserts, cakes and cookies and for sprinkling (with sugar) on porridge. However, it is also excellent with meat, fish, vegetables, rice and beans.