Japanese women's clothes are made of certain materials, colors and designs for cultural reasons and because of the seasons, events and age of the woman wearing them. The traditional styles of clothing in Japan are normally called "wafuku." Spring colors are bright and often floral in pattern. In the cooler months of fall, the colors and patterns change into those from autumn, For example, there may be colored maple leaves in the fall. During winter, particularly as the holidays near, the women may wear "good luck" designs, such as bamboo or pine trees. As the days become cooler, the materials become heavier or are lined. Older women, especially seniors, wear darker colors or black. Different materials and designs are also used for special days when there are ceremonies and religious holidays. Although most Japanese women now wear Western-style clothing most of the time, they will still wear their traditional attire certain times of the year.
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eHow Article: About Japanese Clothing