Regional Edge Functions are a new feature introduced by Vercel that allow developers to specify the region their Edge Function executes in, enabling them to run functions near their data sources to avoid high-latency waterfalls and ensure users have the best experience possible. This capability is particularly useful for rendering sites and avoiding "waterfalls" where multiple queries from a database add up to slow page loading times. By moving computing resources closer to data sources, edge computing reduces latency and provides faster cold start times. Regional Edge Functions can be configured to run globally or nearest to the user, providing users with the lowest latency and best experience on their site.