古罗马帝国的骑士彼此相遇时要举起面甲,以表示敬意,显示骑士精神,同时亦向对方显示脸部,以免被自己人误杀。到了中世纪,西欧的武士们都去掉了面甲,举面甲的传统演变为脱下头盔或帽子。英国资产阶级革命以后,正式把脱帽敬礼的传统改为用于接触帽沿,英国军人敬礼时手心外翻,表示手中无武器,而且双脚并拢,或立正姿式,表示军人的气魄。 Knights of the ancient Roman Empire raised their visors when they met each other, in order to show their respect, to show the spirit of the knight, and to show their faces to each other so that they would not be mistaken by oneself. By the Middle Ages, Western Europe’s warriors had removed their face armor and their nails tradition evolved into taking off their helmets or hats. After the British bourgeois revolution, the tradition of taking off hats was officially changed to be used for touching the brim. When the British soldiers saluted, they turned their hands out of their hands to show that they had no arms in their hands and that their feet were close together or stood upright to show the courage of soldiers.