Xiangqi (; ), also called Chinese chess or elephant chess, is a strategy board game for two players. It is the most popular board game in China. Xiangqi is in the same family of games as shogi, janggi, Western chess, chaturanga, and Indian chess. Besides China and areas with significant ethnic Chinese communities, this game is also a popular pastime in Vietnam, where it is known as , literally 'General's chess'. The game represents a battle between two armies, with the primary object being to checkmate the enemy's general (king). Distinctive features of xiangqi include the cannon (pao), which must jump to capture; a rule prohibiting the generals from facing each other directly; areas on the board called the river and palace, which restrict the movement of some pieces but enhance that of others; and the placement of the pieces on the intersections of the board lines, rather than within the squares. Board Xiangqi is played on a board nine lines wide and ten lines long. As in the game Go (; or Wei ch'i ), the pieces are placed on the intersections, which are known as points. The vertical lines are known as files (), and the horizontal lines are known as ranks (). Centred at the first to third and eighth to tenth ranks of the board are two zones, each three points by three points, demarcated by two diagonal lines connecting opposite corners and intersecting at the centre point. Each of these areas is known as , a castle. Dividing the two opposing sides, between the fifth and sixth ranks, is hé, the "river". The river is usually marked with the phrases , meaning "River of the Chu ", and , meaning "Border of the Han", a reference to the Chu–Han War. Although the river (or Hanchu boundary) provides a visual division between the two sides, only two pieces are affected by its presence: soldiers have an enhanced move after crossing the river, and elephants cannot cross it. The starting points of the soldiers and cannons are usually, but not always, marked with small crosses. Rules The pieces start in the position shown in the diagram above. Which player moves first has varied throughout history and from one part of China to another. Different xiangqi books advise either that the black or red side moves first. Some books refer to the two sides as north and south;