Divans are very common and are less expensive than other types of bed. They are made from wooden covered with material and the mattress sits on top. Many divans come with built in drawers which provide plenty of storage space. Sofa beds are sofas which can convert into beds when required. They are great for spare rooms as they can be kept as a sofa and then pulled down into a bed if you have guests.
Platform bed frames are popular in modern bedrooms for they have simple lines, may not have a box spring and are compact in size. Hence, they are suitable even for homes with smaller bedrooms for they do provide space under the bed to store additional stuff. Those who have the money to go in for higher end platform bed frames can get well-crafted designs that come in many rich finishes and different colors. The Japanese penchant for low furniture is what has inspired the platform bed frame design for most of them are built on clean lines, solid colors and are not very tall.