Grand Cayman is an island in the Caribbean Sea. This is an upscale tourist destination with good beaches being very safe for the tourists. Many ocean cruises make a stop here. However, you should understand, that the Caribbean has many more interesting places both in terms of beaches, as well as for attractions. Shore and seabed: sand, stones. 
Hotels in the Cayman Islands are very expensive and somewhat overpriced. However, the service is of a very high level. Predictably, almost all the hotels are located in the west side of the island, where the beaches are better.