Dart is a programming language developed by Google, and it is used to build web, mobile, and desktop applications. It is an object-oriented, class-based language with C-style syntax. Dart is designed to be easy to learn and use, with features such as garbage collection and a strong type system.

Flutter is a mobile app development framework that uses Dart as its programming language. It was also developed by Google, and it allows developers to build high-performance, cross-platform mobile apps for both iOS and Android. Flutter provides a rich set of pre-built widgets and tools, which makes it easy to build beautiful and responsive user interfaces.

One of the key advantages of using Flutter is its hot-reload feature, which allows developers to see the changes they make to the code almost instantly. This helps to speed up the development process and makes it easier to iterate and refine the app.

Overall, Dart and Flutter are powerful tools for building modern, high-quality applications, and they are widely used by developers all over the world.