This example demonstrates the process of loading and parsing CSV data using D3 v5 and React. It fetches a dataset of CSS named colors from a GitHub gist and displays file size, row count, and column count in a large text element. The code primarily uses `d3.csv` with promise-based `.then()` handling, while commented alternatives show the same task using `fetch` with async/await and `d3.csvParse`. A blocked-out "pyramid of doom" illustrates an outdated nested-callback approach that is avoided.