What is the role of permissions in security and access control systems?

Permissions in Android control the access of applications to protected resources and device features, such as the camera, contacts, or location. They ensure security by preventing unauthorized use of sensitive data or capabilities.

The security system requires that an application requests the necessary permissions in the manifest and, starting from certain Android versions, dynamically at runtime from the user.

For example, to access the camera, an application must declare the permission in AndroidManifest.xml:

<uses-permission android:name="android.permission.CAMERA" />

And then request the permission from the user during runtime if necessary.