The default administrative account in Unix-like operating systems is called root. So, in Linux, the root user has the power to start/stop any system service, edit/delete any file, change the privileges of other users, and so on. We have already learned that Android uses the Linux kernel, and hence, most of the concepts present in Linux are applicable to Android as well. However, most of the Android phones do not let you log in as a root user by default.

Imagine a malicious application having access to an entire Android system with root access. Remember that, in Android, each application is treated as a separate user and issues a UID. Thus, the applications have access to limited resources and the concept of application isolation is enforced. Essentially, rooting an Android device allows superuser capabilities and provides open access to the Android device.