V3: Column simple

HTML

<script src="http://www.amcharts.com/lib/3/amcharts.js" type="text/javascript"></script>
<script src="http://www.amcharts.com/lib/3/serial.js" type="text/javascript"></script>
<div id="chartdiv" style="width: 100%; height: 362px;"></div>

JavaScript

var chart;

var chartData = [{
    "country": "USA",
        "visits": 4025
}, {
    "country": "China",
        "visits": 1882
}, {
    "country": "Japan",
        "visits": 1809
}, {
    "country": "Germany",
        "visits": 1322
}, {
    "country": "UK",
        "visits": 1122
}, {
    "country": "France",
        "visits": 1114
}, {
    "country": "India",
        "visits": 984
}, {
    "country": "Spain",
        "visits": 711
}, {
    "country": "Netherlands",
        "visits": 665
}, {
    "country": "Russia",
        "visits": 580
}, {
    "country": "South Korea",
        "visits": 443
}, {
    "country": "Canada",
        "visits": 441
}, {
    "country": "Brazil",
        "visits": 395
}, {
    "country": "Italy",
        "visits": 386
}, {
    "country": "Australia",
        "visits": 384
}, {
    "country": "Taiwan",
        "visits": 338
}, {
    "country": "Poland",
        "visits": 328
}];


AmCharts.ready(function () {
    // SERIAL CHART
    chart = new AmCharts.AmSerialChart();
    chart.dataProvider = chartData;
    chart.categoryField = "country";
    chart.startDuration = 1;
    chart.angle = 30;
    chart.depth3D = 15;    

    // AXES
    // category
    var categoryAxis = chart.categoryAxis;
    categoryAxis.labelRotation = 90;
    categoryAxis.autoGridCount  = false;
    categoryAxis.gridCount = chartData.length;                    
    categoryAxis.gridPosition = "start";

    // value
    // in case you don't want to change default settings of value axis,
    // you don't need to create it, as one value axis is created automatically.

    // GRAPH
    var graph = new AmCharts.AmGraph();
    graph.valueField = "visits";
    graph.Text = "[[category]]: <b>[[value]]</b>";
    graph.type = "column";
    graph.fillAlphas = 0.8;
    chart.addGraph(graph);

    chart.write("chartdiv");
});