he was a french composer (a composer is an author of music in any form whether vocal, instrumental, electronic, jazz, pop, rap, rock, etc) who’s works were a seminal (aka influential, groundbreaking, original, creative, important, innovative, etc) force in the music of the 1900s/20th century. he developed an original system of harmony and musical structure that many impressionists and symphoniste painters and writers of his time hoped for and loved dearly