With Vercel you can deploy two types of Functions, Edge Functions and Serverless Functions. Both can be deployed without any additional configuration.
They are globally deployed by default when using Next.js, and give you up to 100x faster startups than Node.js on containers or virtual machines. Because they are built on V8, they have zero cold starts.
Serverless Functions can be used to handle user authentication, form submission, database queries, custom slack commands, and more. They are run on the Edge Network and available with next to no configuration.