JSX is a syntax extension for JavaScript that lets you write HTML-like markup inside JavaScript. It gets compiled to React.createElement() calls.

Props (short for properties) are used to pass data from parent to child components. They are read-only and help make components reusable.

Props are immutable - a component must never modify its own props. If you need mutable data, use state instead.

The map() method is used to render lists in React. Each item must have a unique 'key' prop to help React efficiently update the DOM.

The special 'children' prop contains whatever JSX is placed between a component's opening and closing tags, enabling flexible component composition.