A large portion of Japanese interior walls are often made of "shōji" screens that can be pushed open to join two rooms together, and then close them allowing more privacy. The "shōji" screens are made of paper attached to thin wooden frames that roll away on a track when they are pushed. Another important feature of the "shōji" screen, besides privacy and seclusion, is that they allow light through. This is an important aspect to Japanese design. Paper translucent walls allow light to be diffused through the space and create light shadows and patterns.