jquery的data方法作何用?

 $.ajax({type: "post",url:"xxxxxxxxxxx.jsp", data:{name:"张三",timeout:5000,beforeSend: function(XMLHttpRequest){
                                    },success: function(data, textStatus){
                                       
                                    },
                                    error: function(XMLHttpRequest, textStatus, errorThrown){
                                     
                                    }});