The senior two ranks of Knight or Dame Grand Cross, and Knight or Dame Commander, entitle their members to use the title of Sir for men and Dame for women before their forename, if citizen in a country with Queen Elizabeth II as Head of State.
Most members are citizens of the United Kingdom or the Commonwealth realms that use the Imperial system of honours and awards.
Honorary knighthoods are appointed to citizens of nations where the Queen is not head of state, and may permit use of post-nominal letters but not the title of Sir or Dame.
King George V founded the Orders to fill gaps in the British honours system:
The Order of the Bath honoured senior
military officers and civil servants;
The Order of St Michael and St George honoured diplomats and colonial officials;
rder of the Indian Empire honoured Indian rulers and British and Indian officials of the British Indian Empire; and
The Royal Victorian Order, in the personal gift of the monarch, honoured those who had personally served the royal family.
The Most Noble Order of the Garter founded by Edward III in 1348 and regarded as the most prestigious British order of chivalry (though in precedence inferior to the military Victoria Cross and George Cross) in England and the United Kingdom.
It is dedicated to the image and arms of Saint George, England's patron saint.
Most Excellent Order of the British Empire is a British order of chivalry, rewarding contributions to the arts and sciences, work with charitable and welfare organisations, and public service outside the Civil service
1.Knight Grand Cross or Dame Grand Cross of the Most Excellent Order of the British Empire (GBE) = Sir /Dame
Sir/Dame if inhabitant of a country which has Queen Elizabeth II as head of state
2. Knight Commander or Dame Commander of the Most Excellent Order of the British Empire (KBE or DBE) = Sir /Dame
3. Commander of the Most Excellent Order of the British Empire (CBE)
4. Officer of the Most Excellent Order of the British Empire (OBE)
5. Member of the Most Excellent Order of the British Empire (MBE)