> `ReactTransitionGroup` and `ReactCSSTransitionGroup`are both deprecated as of React v15.5.0. The recommendation is to use `TransitionGroup` and `CSSTransitionGroup` from [`react-transition-group`](https://github.com/reactjs/react-transition-group) instead.
> `ReactTransitionGroup` and `ReactCSSTransitionGroup`have been moved to the [`react-transition-group`](https://github.com/reactjs/react-transition-group/tree/v1-stable) package that is maintained by the community. Its 1.x branch is completely API-compatible with the existing addons. Please file bugs and feature requests in the [new repository](https://github.com/reactjs/react-transition-group/tree/v1-stable).
The [`ReactTransitionGroup`](#low-level-api-reacttransitiongroup) add-on component is a low-level API for animation, and [`ReactCSSTransitionGroup`](#high-level-api-reactcsstransitiongroup) is an add-on component for easily implementing basic CSS animations and transitions.
The [`ReactTransitionGroup`](#low-level-api-reacttransitiongroup) add-on component is a low-level API for animation, and [`ReactCSSTransitionGroup`](#high-level-api-reactcsstransitiongroup) is an add-on component for easily implementing basic CSS animations and transitions.