Cocoa butter is a key ingredient in making chocolate. It's also used to make some toiletries, ointments, and pharmaceuticals.
In Chocolate Edit
There are different laws around the world about how pure the cocoa butter should be: In the US, there must be 100% (or 99.999999999...%) pure cocoa butter for it to be called chocolate. In the European Union, the amount of alternative fats cannot exceed 5%.
In Pharmaceuticals Edit
Its melting temperature is at body temperature, so it melts easily. Its fragrance and softness makes it useful for soaps, where it is very popular.