Vibed to Cracked
Sign In

React

useEffect

Definition

A React hook for performing side effects in function components — fetching data, setting up subscriptions, or manually updating the DOM. Runs after every render by default; use the dependency array to control when it runs.

Code Example

Jsx

Learn More

Fundamentals tutorials

Related Terms

Component

A reusable, self-contained piece of UI in React. Components accept inputs (props) and return JSX describing what should appear on screen. Can be functions (recommended) or classes.

State

Data that a component manages internally and can change over time. When state updates, React re-renders the component. Use useState for simple state and useReducer for complex state logic.

useMemo

A React hook that memoizes the result of an expensive computation, recomputing only when its dependencies change. Use it to optimize performance by avoiding unnecessary recalculations on every render.