Four colors prevail on the flags of modern Islamic states: green, red, black and white. In the Middle Ages, they were symbols of various religious and political parties: the banner of Muhammad and the Umayyad caliphs was green; black – for the rebels in 750 and for the Abbasid caliphs; white – among the Shiites and Fatimid caliphs (Alids) in Egypt; the red banner was first among the Kharijites (military democrats), later it was taken over by the Turks when they converted to Islam.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.