A component is a reusable piece of UI. It can be a class or a function that returns JSX. Components manage their own state and can receive data through props, allowing you to build complex interfaces by combining smaller pieces.

State is managed within a component. It can change over time and re-render the component. Props are passed from parent to child components and help maintain a unidirectional data flow, making React predictable.

Hooks are functions that let you use state and lifecycle features in functional components. Examples include useState for managing state and useEffect for side effects, enabling you to write more concise code without classes.

Expo is a framework and platform for universal React applications. It provides tools and services to build, deploy, and iterate on apps quickly without worrying about native development, making it more accessible for beginners.