This example shows the 2020 populations of 30 countries as a horizontal bar chart. The visualization uses SVG rendering through React, with D3 version 5 APIs including `scaleBand`, `scaleLinear`, and `max` to map values. A `csv` loader fetches data from a remote GitHub-hosted file. Bars are drawn as `<rect>` elements via the custom `Marks` component, with axes generated by `AxisBottom` and `AxisLeft`. Tick labels use the `format` function to abbreviate large numbers.