Aquarium Corals by Eric H. Borneman is what you would call the coral keeper bible. Its not going to tell you X coral needs X watts of light or anything but it will give you information about keeping corals. You can find this book in our saltwater library convently linked to Amazon.
Soft corals are just that. Soft They have no real hard skelital structure. Hard corals have a hard calicified coral skeliton that the coras itself live in and build.
__________________ Remember dont tap the glass, your fish will think you're an idiot-Anonymous mother
once there click on the animal library link on the bottom of the page..
once at that page scroll down to the bottom of the page, there will be a babblefish icon, altivista.com's translator, there is a square with a arrow pointing to the right in it.. click the arrow and it will take you to the photo/library of fish/inverts/and coarls.. they are organized in hard and soft corals.. the SPS coarls are mixed with the LPS in the hard coarls section.. he gives a general idea of care and needs of the coarls as well..
HTH