Glossary

Impeller is Flutter's high-performance rendering engine, built from the ground up for Flutter's needs and modern graphics APIs.

Its primary goal is to provide consistently smooth performance and eliminate stuttering while rendering, particularly that caused by shader compilation during animations and interactions.

Impeller achieves this by pre-compiling a specific, smaller set of shaders at application build time, rather than compiling at runtime.

An immutable description of part of a user interface.

In Flutter, almost everything is a widget. Widgets are the fundamental building blocks you use to create your application's UI with Flutter. Each widget is an immutable declaration of _what the UI should look like based on its current configuration and state.

Widgets are composed together in a hierarchy to form the widget tree. When a widget's state changes, the Flutter framework rebuilds the necessary parts of the tree to update the UI.

There are two primary types of widgets, including StatelessWidget, which have no mutable state, and StatefulWidget, which have a persistent state that can be updated.