(August 25, 1918 – October 14, 1990) LEONARD BERNSTEIN...was an American conductor, composer, author, music lecturer and pianist. He was the first conductor born and educated in the United States of America to receive world-wide acclaim. He is perhaps best known for his long conducting relationship with the New York Philharmonic. Orchestras all over the country are looking back on the life and legacy of the late Leonard Bernstein this year in observance of his 90th birthday. Last winter, the Philadelphia Orchestra hosted a festival of star performances, premieres and seminars. Bernstein's birthday party continues this week when the Boston Pops Esplanade Orchestra returns to Verizon Hall, to play a program titled "Make Mine Bernstein."