sudoku
n.
A logic-based placement puzzle in which numbers must be fit into a 9x9 grid such that each numeral appears exactly once in each row, column and each of nine 3x3 blocks.
The name "Sudoku" is from Japanese 数独, meaning "the digits must occur only once".
Sudoku was invented by an American but popularized by the Japanese.
Also known as Number Place.
Gomoku
n. Japanese transliteration
Also known as gobang. It is an abstract strategy board game. It is traditionally played with go pieces (black and white stones) on a go board (19x19 intersections); however, because once placed pieces are not moved or removed from the board, gomoku may also be played as a Paper and pencil game.
Black plays first, and players alternate in placing a stone of their color on an empty intersection. The winner is the first player to get an unbroken row of five stones horizontally, vertically, or diagonally.
Gomoku is known in Korean by its cognate Omok and in Chinese as Wuziqi.