This code is only valid in United Kingdom and will be used by British officials amongst themselves when the Queen dies. Her private secretary has the duty of calling the British Prime Minister with the news in a coded message. The message is coded to keep the news from leaking. The protocol says that the heads of every commonwealth nations will be informed first and media will be told next and allowed to make the news public.
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There are many color based codes like:
‘Code Black’- used by military to signify a bomb threat. ‘Code Purple’ is to signify child abduction and ‘code pink’ is used to notify of infant abduction. ‘Code Yellow’ is known in hospital for missing patients and also to alert the staff to be ready to face an external disaster.
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Mayday is probably the most recognized and dreaded code words in the world. It signifies that a plane or ship is in distress. It originated in 1923, when a radio officer Fredrick Mockford in Croydon airport in London requested to form a single word that is easy to understand by all officials and pilots in emergency situations. Mockford used ‘mayday’ keeping both English and French languages in mind.
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