Pocketed Coil is a product of Simmons. Each individually wrapped Pocketed Coil moves independently, so you sleep peacefully even if your partner tosses or turns. Pocketed Cable Coil provides the ultimate in motion reduction and durability.

A Divan bed consists of a mattress and a box spring, a large mattress-sized box containing wood and springs that provide additional support and suspension for the mattress. Optional headboard is needed to attach to the head of the bed.
You can buy this type of bed from Simmons, Sealy, Nobles (Japan Bed), and France Bed (Japanese manufacturer)
Divan also means daybed.

This type consists of bed frame and mattress.

There are several types of the sofa bed. Some has mattress and iron frame stored inside sofa seat. Some has a back which can be reclined to be flat.

A Bunk Beds two or more beds one atop the other, handy when you have two children who need to share a bedroom.

Baby bed is for new-born baby up to 1 year old. The height is suitable when changing diapers. some baby beds has storage under the bed, but try to secure some space to allow the air flow.
Baby beds are used for only a year or so, rental is a convenient way to save space.

A flat sheet covers mattress and are used with blanket or comforter. You can easily find Single size, Double size, but only limited shops carry Queen size and King size sheets in Japan.

Ends of the sheets have elastics to fit to the mattress, so we can make a bed faster than using a flat sheet.

Comforters are not thick like Futon and sometimes used as a bed cover.
Stuffed with feather or polyester cotton.

Feather pillows are costly and sometimes cause allergy. Polyester pillows are easy to maintain, and some are washable.
Wide variety of pillows with different materials are available in Japan.

Futon means traditional beddings in Japan. Japanese Futon consists of Kake-futon, which serves like comforter, and Shiki-futon, which serves as mattress, basically to put on the Tatami mat. Futons are stuffed with cotton, polyester, or feather.