Why is it necessary to specify core application components in the manifest file in Android?

In Android, the manifest file (AndroidManifest.xml) serves as the central description of the application for the system. It is necessary to specify the main components of the application (Activity, Service, BroadcastReceiver, ContentProvider) because:

• The Android system uses the manifest to register components and manage their lifecycle.
• The manifest defines which components are available for launch, which have certain permissions, and how they interact with the system and other applications.
• Without declaring components in the manifest, the system will not be able to detect and launch them.

For example, if an Activity is not declared in the manifest, the application will not be able to open that screen. The manifest can also specify intent filters, permissions, themes, and other settings necessary for the proper functioning of the application.