Irving Berlin (1888-1989) was the most successful songwriter of the 20th century. Though, like his contemporaries, he spent the better part of his career writing songs (usually both words and music) to be used in Broadway musicals, he is better remembered for the songs themselves than for the shows (and sometimes films) in which they were introduced. This is because Berlin was a master at the kind of music that flourished from the turn of the century until World War II, shows that were really just collections of production numbers, scenes, and novelty acts (organized vaudeville presentations, really) rather than the story musicals that became prevalent starting with Rodgers and Hammerstein's Oklahoma! in 1943. It is also because Berlin, who did not read music and could play the piano in only one key and only on the black notes (he used a special piano with a lever that changed keys for him and employed a musical secretary to notate his compositions), wrote songs, not scores.