A bar chart displays twenty data values as vertical bars with numeric labels. Clicking the text triggers a five-second transition that updates the bars and labels with new data. The visualization uses D3 v4.5.0 with `scaleBand` for the x-axis, `scaleLinear` for the y-axis, and `transition().duration(5000)` to animate both `rect` heights and `text` positions. The labels move and change numbers smoothly alongside the bars, demonstrating coordinated transitions across SVG elements.