Twin/Single - This size is perfect for children sleeping in a small room and easily fits in spare guestrooms. Standard size is 39 in. wide by 75 in. long.
Full/Double - This size is 15 in. wider than a twin, but if two people sleep in it, each person gets less room than a twin offers for one person.
Queen - This size is wider than a full/double, by 6 in. thereby providing more room for each person or lots of room for one.
King/Eastern King - This size is wider than a Queen by 18 in., but is the same length, providing more elbow room.
California King/Western King - This is the longest bed available, perfect for tall people or those who want maximum room. It is the same width as a standard King, but 4 in. longer.