This paper considers the structures used today in the maritime and ocean industries to accommodate people in semi- permanent accommodation at sea: the floating hotels, or flotels. They have mainly been developed to support the activities of the offshore oil & gas industry, although in coastal areas they are widely used for several purposes, mainly as commercial hotels, but with a quite different philosophy of use. The objective of the paper is to show how the term flotel is used to denominate very different craft that, while serving the same purpose (provide floating accommodation), have a totally different configuration according to the place where they are located: in protected waters in coastal areas (where the craft are sometimes called coastels), in benign and shallow waters of the open ocean or in the harsh environments of deep waters, etc.