Edit in JSFiddle

var data = [];
for (var i = 0; i < 100; i = i + 5) {
    data.push(i);
}
displayArray(data);
$('#output').append('Lets start Parallel Processing' + dateOutput() + '<br/>');
async.filter(data, processData, function (result) {
    $('#output').append('<br/>Parallel Processing Done At ' + dateOutput() + '<br/>');
    displayArray(result);
    $('#output').append('Lets Start Same Operation In Series ' + dateOutput() + '<br/>');
    async.filterSeries(data, processData, function (result) {
        $('#output').append('<br/>Series Processing Done At ' + dateOutput() + '<br/>');
        displayArray(result);
    });
});

function processData(item, callback) {
    //simulate a time taking task
    $.ajax({
        dataType: "json",
        url: '/echo/json/',
        type: 'post',
        data: {
            delay: 1,
            json: $.parseJSON(item)
        },
        success: function (item) {
            $('#output').append('.');
            if (item % 2) {
                callback(true);
            } else {
                callback(false);
            }
        }
    });
}

function displayArray(to_display) {
    $('#output').append('Our Array<br/>');
    $('#output').append('====================<br/>');
    for (var i = 0; i < to_display.length; i++) {
        $('#output').append(to_display[i] + ",");
    }
    $('#output').append('<br/>' + '====================' + '<br/>');
}

function dateOutput() {
    var date = new Date();
    return date.getHours() + ":" + +date.getMinutes() + ":" + +date.getSeconds();
}