Japan is a country with a lot of old traditions still preserved in today's society. This is also true for the different types of kimonos that are in existence. Unlike what some might think there are different types of kimonos, with different names, different meanings and different purposes - worn by both men and women. This is the yukata (浴衣), perhaps the most common and simple version of the kimonos.
The name is really a abbreviation of yukatabira, which means bath underclothing. The origin of the garment can be traced back to at least the Heian era (794-1185) when noble women wore yukata, made of linen, after taking baths. It is still a favourite garment when visiting Japanese inns and spas for recreation.
Today the yukata is first and foremost the informal kimono of the summer. It had a big revival in the 1990's and the popularity still stands. Girls and women are wearing it as casual wear, and to festivals (a very popular theme in shoujo-manga - manga for girls). They are made out of light cotton and can be worn with an ordinary sash, like on the picture, and not just the much more complicated obi - which means that it is possible for a woman to put it on herself.
The yukatas are available in almost any pattern, but there are general rules that most people adhere to. The younger the wearer the more bold both patterns and colours. Grown-up women generally have a much more sober ones, in dark colours with geometrical patterns, children can have really daring fabrics and young girls often have a floral pattern and softer colours.