Two interactive bar charts present data for three groups (A, B, C) across two datasets. Users switch between the "Taxis" and "Personenautos" datasets via buttons, triggering a smooth transition animation that updates the bar heights. Built with D3 v5, the visualization uses `d3.scaleBand` and `d3.scaleLinear` for axes, while the `transition()` method animates rectangle attributes over one second. SVG rendering handles the graphics, and the update function leverages D3's enter/merge/exit pattern to efficiently redraw bars.