"國家元首" refers to the head of state in a country, who represents the nation in official capacities. This role can vary significantly depending on the country's political system. In some nations, the head of state is a monarch, such as a king or queen, while in others, it may be an elected official, like a president. The responsibilities of a "國家元首" often include signing legislation, conducting foreign affairs, and serving as a symbol of national unity. In parliamentary systems, the head of state may have limited powers, while in presidential systems, such as the 美國 or 巴西, the head of state often holds significant executive authority.