Pianist Lang Lang, who is also a UN Messenger of Peace, speaks during a press conference prior to a concert entitled "Lang Lang and Friends" in commemoration of the UN Day, at the UN headquarters in New York, on Oct. 24, 2014. The United Nations celebrated its 69th birthday with its messenger of peace, world-renowned pianist Lang Lang performing at a concert on Friday evening. (Xinhua/Niu Xiaolei)