Documentation is mysterious

[lommaj]

on the front page of this site you have this code. Where is "Line" defined, core? basic? I cant seem to find anything related to this anywhere or any documentation related how to replicate something like this very first example on your site.

  <Chart
    width= {width}
    height= {height}
    data= {data}
    chartSeries= {chartSeries}
    x= {x}
    >
    // build line chart
    <Line
      chartSeries= {series1}
    />
    // build area chart
    <Area
      chartSeries= {series2}
    />
    <Xaxis/>
    <Yaxis/>
    <Xgrid/>
    <Ygrid/>
  </Chart>