React

Component What kind of JavaScript value does React actually accept as a renderable description?
Renderer How does that description become a real DOM node?
JSX If React wants element objects, what exactly is JSX syntax doing?
Props If a component is just a type in an element, how does data get into it?
Events If UI descriptions are static values, how does user interaction enter the system?
State If props come from outside, where does changing local data live?
Conditional rendering If components return descriptions, how do different branches of UI appear from ordinary JavaScript conditions?
Lists and keys If data produces many sibling elements, how does React keep those children identified across renders?
Fragments How can a component return sibling elements without adding an unnecessary DOM wrapper?
Forms If input elements keep their own DOM state, how does React keep form data in component state instead?
Render & commit The boundary between pure rendering and host-side mutation
Reconciliation Once something is already on the page, how does React update it without rebuilding everything?
Hooks Where can stateful behavior live?