Water beds are just that - beds filled with water! There are two types of water bed, soft sided water bed or hard sided water bed. The more expensive water beds are made to lessen the wave effect which was common in the early models. Water beds are usually heated and a thermostat controls the temperature.
While it’s an old trend, it is still, and will continue to be popular. It’s a very safe option if you plan not to change the decor of the room for generations as it doesn’t have a time stamp on it. Think of the interior design trends of the 60’s and 70’s, they went out of fashion and aged which requires an remodeling at some point. A room like the one below is timeless. The room will have to be touched up to keep it fresh but the general underlying design of the room remains. The arm chair and foot rest, pillows and even the drape around the bottom of the bed are floral, which is a massive trend in 2014, therefore, even a room which is traditional could be accessorized with fixtures and fittings which are in vogue, so long as they complement the principles of the room.