what is the difference between a black tie and white tie event
From the 1920s onward black tie slowly replaced white tie as the default evening wear for important events, so that by the 21st century white tie had become rare. White tie nowadays tends to be reserved for special ceremonies -- especially state dinners -- and a very select group of social events such as the Al Smith Memorial Dinner in New York, the Commemoration balls at Oxford University, certain May Balls at Cambridge University, the June ball at Durham University, the Christmas ball at Buckingham Palace, dinners of certain American hereditary societies, and very formal weddings. The Vienna Opera Ball and the Nobel Prize ceremony are white tie events, and some European universities retain it as the dress code for doctoral conferment ceremonies.