In Flutter, packages and plugins are both used to extend the functionality of the framework and provide additional features to developers.

A package in Flutter is a collection of related classes, functions, and other resources that can be easily shared and reused across different projects. Packages can be published and distributed through the Flutter package repository, making it easy for developers to discover and use them in their projects. Many commonly used packages, such as `http`, `shared_preferences`, and `provider`, are available through the Flutter package repository.

Plugins, on the other hand, are packages that provide access to platform-specific APIs and services, such as camera, sensors, location, and contacts. Plugins are typically used to integrate native functionality into Flutter apps, allowing developers to create apps with native-like performance and behavior. Plugins are typically developed by the Flutter community or third-party developers and are published through the Flutter plugin repository.

Plugins are implemented using a combination of Dart and platform-specific code, such as Kotlin or Swift. This code is typically bundled as a native library, which is then accessed by the Flutter app through a platform channel.