This example displays summary statistics for a CSV dataset of all space missions from 1957, showing the file size in kilobytes, row count, and column count in large text. It loads the data using `d3.csv` with a promise, then calculates the metrics via `d3.csvFormat` and the parsed data’s `length` and `columns` properties. The code also includes commented alternatives using `fetch` with `async/await` and `d3.csvParse`, as well as a nested promise “pyramid of doom” pattern. The data source is a raw GitHub Gist URL.