Wikipedia
are Japanese playing cards. Playing cards were introduced to Japan by the Portuguese traders during the mid-16th century. These early decks were used for trick-taking games. Karuta packs are divided into two groups, those that are descended from Portuguese cards and those from Eawase. Eawase was originally played with shells but were converted to card format during the early 17th-century. Chinese playing cards of the money-suited and domino types existed in Japan from at least the late 18th century until the early 20th century. Their games would influence those played with the Hanafuda pack.
The basic idea of any Eawase karuta game is to be able to quickly determine which card out of an array of cards is required and then to grab the card before it is grabbed by an opponent. There are various types of cards which can be used to play karuta. It is also possible to play this game using two standard decks of playing cards.
The two types of Eawase karuta decks that are most often seen are the "uta-garuta" and "iroha-karuta". In " uta-garuta", players try to find the last two lines of a waka given the first three lines. It is often possible to identify a poem by its first one or two syllables. The poems for this game are taken from the Ogura Hyakunin Isshu and are traditionally played on New Year's Day.
Anyone who can read hiragana can play " iroha-karuta" (いろはかるた). In this type, a typical torifuda features a drawing with a kana at one corner of the card. Its corresponding yomifuda features a proverb connected to the picture with the first syllable being the kana displayed on the torifuda. Karuta is often played by children at elementary school and junior high-school level during class, as an educational exercise. Although several kinds of Karuta games are described below, in reality any kind of information that can be represented in card form can be used including shapes, colours, words in English, small pictures and the like.