A component is a function that returns JSX. The "use client" directive that makes one interactive is explained in Component Authoring.

export function Greeting({ name }: { name: string }) {
  return <h1>Hello, {name}</h1>
}

#Pages

Topic Description
Component Authoring Server vs. client components, composition, props, refs
Children & Slots The children prop, Slot, and asChild
Context API createContext / useContext; sharing state across files
Portals Rendering elements outside their parent DOM hierarchy
Style Overrides User classes override base classes via CSS Cascade Layers