Until fairly recent in the history of our islands, one would not be able to tell if the lump of brown sugar (often shaped in a coconut shell half) was made from coconut, nipa, buri, kaong, or sugarcane. All but coconut and cane remain mainstream, and we are glad that the health industry has pushed this particularly tropical-tasting, low glycemic gem into our nation's consciousness.
Coconut sugar is made from the cooked-down nectar of the coconut palm tree. It is less cloying than cane sugar, and can be used for pretty much all normal sugar applications, though there is that great coconutty taste to contend with. We use it in everything--coffee, cacao, rice cakes, baked goods, calamansi juice.
Has a low glycemic index, so diabetics can enjoy it. Just remember though, sugar is sugar, so never overdo it!