This visualization demonstrates a left join operation between COVID-19 datasets, using New York Times rolling averages for cases and deaths alongside Our World in Data vaccination rates. The code loads both CSV files via `d3.csv` promises, parses numeric fields, and implements a custom `joinTables` function that matches rows on a shared date key. A static test dataset pairs articles with brands to validate the join logic. The page displays minimal text, with commented-out code showing a potential scatterplot visualization that would compare vaccination percentages against case averages per 100,000 people.