[fire_lake]

Functional Components are not functional in the sense of functional programming. They are shared mutable state.

[patates]

Function-based components. They have vaguely functional aspects but they are not functional indeed. I think most people say functional because "function-based" is too long.

[lastdong]

If I recall correctly we have stateless functional components (not managing any state). Functional in React should mean immutable state.