Frontend frameworks often use the mental modal that a component (or entire UI) is the result of running state through a pure function. Dan Abromov shares his thoughts on the current state of React with server components.

UI = f(data)(state)

Here's how I interpret it: in the mental model we're used to, a component is a pure function that returns UI based on its props. In this case, a Greeter is rendered on the client.

function Greeter(props) {
  return <p>Hello, {props.name}!</p>;
}

Say we have a server component that know who needs to be greeted before the code hits the client. In that case, the name will come from data available on the server.

function Greeter(data) {
  return function () {
    return <p>Hello, {data.name}!</p>;
  }
}

The outer function is executed on the server, the inner on the client.

The true power lies in mixing and matching the paradigms. Say you want to read a translation string on the server, and greet a name on the client.

function Greeter(data) {
  return function (props) {
    return <p>{data.translations.hello}, {props.name}!</p>;
  }
}