explain this jquery code please

Question

please explain this code what is label:item.split and all 

 

function (data)

{

if (data.d.length > 0)

{

response($.map(data.d, function (item)

{

return {

label: item.split('/')[0],

val: item.split('/')[1]

}

}));

}

else {

response([{ label: 'No Records Found', val: -1 }]);

$('#txtSearch').val('');

}

}

Thanks in advance