This example demonstrates a streaming bar chart that updates every 1.5 seconds by shifting the first data point and pushing a new random value onto the end of an array. It shows the classic D3 data-join pattern using `.enter()`, `.update`, and `.exit()` to manage div elements with the class `h-bar`. The code uses `d3.select` and `data()` binding to set each bar’s width and display its numeric value in a span. The visualization relies on `setInterval` to trigger re-renders, with the bars growing and shrinking as the dataset evolves.