If there is any reason why rice is so remarkable it is for being the universal food that supplies two-thirds of the world, cultures that have their own ways of production and eating, united in the traditions that are part of a world cultural heritage. After wheat it is the main cereal consumed and the basis for preparing thousands of recipes, as a main dish, an accompaniment and as a dessert. Belonging to the grass family, rice is typical in temperate, humid zones, and grows in lagoons flooded with water. It began to be cultivated about 6,000 years ago, after two species were domesticated,: Ouryza sativa, native to South and Southeast Asia, whose ancestor was the wild Ouryza rufipogon, and the African, or Ouryza glaberrima, grown initially in the Niger Delta . Over the centuries, the Arabs introduced it into Egypt, the East African coast, in Morocco and also in Spain, after conquering the peninsula in 711. The Asian species gave rise to two great strains of rice, Indica and Japonica. The first is long grain and comprises 80% of rice in the world, while the japonica variety is a medium or round grain. The countries of northern Europe consume mostly Indica rice, a preference that has been progressively extending to the south. For this reason, Europe, traditionally a producer of japonica rice, has converted its farms to the other variety. Currently, rice is grown on all continents, although the main producer in the world is China, which produces 30% of the world's total. In Europe, Spain is one of the producing countries, together with Italy, Portugal, Greece and France. In Spain, there is significant production in the Comunidad Valenciana, Murcia, Catalonia, Extremadura, Andalucia and the Ebro Valley. In Asia alone, more than 2,000 million people obtain 70% of their calories from this cereal, while in Africa it is the most rapidly growing source of food. Moreover, it is a very important product for the food security of low-income food-deficit countries. Almost a billion households in Asia, Africa and America depend on rice field systems as the main source of income. In many places rice replaces the bread consumed daily as the accompaniment of western food. In Japan it is customary to offer a bowl of white rice on sitting at a table although, on the other hand, they do not serve bread. This is a very versatile food that allows any kind of preparation, accompanied by vegetables, fish, meat and eggs. It can be served hot or cold and it is possible to salt it, sugar it, season it with different spices … Furthermore it is customary to use it in cake making. If milled, you get a flour that is used to thicken sauces, creams and fillings for cakes, especially suitable for people intolerant to gluten. However, rice is not only a vital food, but also is the cornerstone of many cultivations and traditions around the planet. It is present in religious ceremonies, festivals, customs, dishes and festivities that revolve around this cereal such as the custom imported from Asia of throwing rice, regarded as a symbol of fertility, at weddings. The UN declared 2004 the International Year of Rice: "Symbol of cultural identity and unity among peoples."