Popular music(流行音乐，可简作pop),in its widest sense,embraces(包含)many genres(类型)of music.The American,especially African American,cultures have been very influential(有影响力的)on pop,Jazz(爵士乐)and Big Band(爵士乐团)music benefited(受益于)from the im-mense popularity(普及)of radio,whilst the war years also confirmed the status(确立地位)of singing stars like Bing Crosby and Vera Lynn.