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Important Components of Android

  The android have lot of components, but the following component are very important and these components are  frequently used for application development.
1. Activity
  The building block of the user interface is Activity. The activity is just like a Window or Dialog in windows application or swing based application.

2. Content Providers
  The content providers provide a standard way for accessing data from storage such as contact details, messages, etc. The data normally shared by more than one application for better storage maintenance.

3. Intents (Notification Manager)
  Intents are systems messages running around the inside of the device. It’s notifying about systems changes such as hardware changes as well as application state changes. Example, Battery level, Signal level etc..,

4. Services
   Activity, Content providers, Intents are short lived and it can be shut down at any time. But the services are independent of any activity and designed for keep running, if needed. The service does not provide a user interface, for example the service might play the music in the background while the user is in a different application.

  In later I will tell the information and purpose of some other components.

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