The current flag of Iran was aopted on July 29, 1980, and is a reflection of the changes brought to Iran by the Islamic Revolution. The basic design of the flag is three horizantal bands of green above white above red, symbolizing vigour, peace, and courage. The traditional green, white, and red of the Iranian flag date back to the 18th century, although there is no agreed explanation of the colors. The colors were arranged in horizontal stripes in 1906. In 1980 a new flag was introduced with the additional emblems expressive of the Islamic Revolution. The emblem in the center of the flag is a highly stylized composite of various elements representing different facets of Islamic life: Allah, the Book, the Sword, the five principles of Islam, balance, unity, neutrality, and the universal government of the downtrodden. Along the edges of the green and red stripes appears a stylized version of the Kufic script used for the Qur'an. The phrase Allahu Akbar ("God is Great") is repeated 22 times. This is the date in the Islamic calendar on which Ayatollah Khomeini returned from exile in 1979.