are vernacular houses constructed in any one of several traditional Japanese building styles. In the context of the four divisions of society, were the dwellings of farmers, artisans, and merchants (i.e., the three non-samurai castes). This connotation no longer exists in the modern Japanese language, and any traditional Japanese-style residence of appropriate age could be referred to as . are characterized by their basic structure, their roof structure, and their roof shape. developed through history with distinctive styles emerging in the Edo period. Types The term literally means houses of the people. It covers houses that accommodated a wide variety of people from farmers to village headmen, merchants and low level samurai. come in a wide range of styles and sizes, largely as a result of differing geographic and climatic conditions as well as the lifestyle of the inhabitants. They generally fall into one of four classifications: farmhouses town houses , fishermen's dwellings and mountain dwellings . Unlike other forms of Japanese architecture (such as those of the style), it is the structure rather than the plan that is of primary importance to the . are divided up with primary posts that form the basic framework and bear the structural load of the building; secondary posts are arranged to suit the functional arrangements of the plan. Despite the wide variety of , there are eight basic forms: The 'inverted U' consists of two vertical posts fixed at the top with a horizontal beam; these units can then be joined with side girders. The beam can be fixed to the top of the post either by resting upon it or via a mortise and tenon joint. This latter method is often found in on the island of Shikoku. The 'ladder' has post and beam units connected with larger beams including beams that are closer to the foundation level. This form of structure originated in townhouses of the Edo period. The system allows the irregular placement of posts and, therefore, allows flexibility in the plan. With the 'umbrella' style, four beams radiate out from a central post. These posts sit at the centre of the square rather than the corners. of this type are often found in Shiga Prefecture. The 'cross' has two beams at right angles to one another with the posts in the centre of the sides. It is often used for very small that have no other posts erected