<P> The emblems of the International Red Cross and Red Crescent Movement, under the Geneva Conventions, are to be placed on humanitarian and medical vehicles and buildings, and to be worn by medical personnel and others carrying out humanitarian work, to protect them from military attack on the battlefield . There are four such emblems, three of which are in use: the Red Cross, the Red Crescent, and the Red Crystal . The Red Lion and Sun is also a recognized emblem, but is no longer in use . </P> <P> There were also prior disputes concerning the use of a Red Star of David by Magen David Adom (MDA), the Israeli first - aid society; the Red Crystal was created in response to these disputes, thus enabling the admission of MDA to the movement . </P> <P> In popular culture, the red cross symbol came to be a recognisable generic emblem for medicine, commonly associated with first aid, medical services, products, or professionals; it has been misused in toys, movies, and video games, outside its defined context . After objections from the Movement, derivatives and alternatives are used . Johnson & Johnson had registered the symbol for their medicinal products . The appropriation of the symbol has led to further confusion when first aid teams and ski patrols in the United States reverse the symbol--a white cross on a red background--thus suggesting an affiliation with Switzerland by simply re-applying the original idea of the red cross symbol, namely by reversing the red cross symbol's colors . </P> <P> The symbols described below have two distinctively different meanings . On one hand, the visual symbols of the Red Cross, the Red Crescent, the Red Lion with Sun and the Red Crystal serve as protection markings in armed conflicts, a denotation which is derived from and defined in the Geneva Conventions . This is called the protective use of the symbols . On the other hand, these symbols are used as distinctive logos by those organizations which are part of the International Red Cross and Red Crescent Movement . This is the indicative use of the emblems, a meaning which is defined in the statutes of the International Movement and partly in the third Additional Protocol . </P>

Why is red cross sign used by doctors and ambulances
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