Server Functions allow Client Components to call async functions executed on the server.
A Server Function can be defined with the React 'use server' directive.
Server Actions are asynchronous functions that are executed on the server. They can be called in Server and Client Components to handle form submissions and data mutations in Next.js applications.
According to react documentation If a Server Function is passed to an action prop or called from inside an action then it is a Server Action
A Server Action can be defined with the React 'use server' directive.