**What is Android?** Android is *an open source, Linux-based software stack.* **What are the six layers of the Android software stack?** The six layers of the Android software stack are: 1. System apps. 2. Java API framework. 3. Native C / C++ libraries. 4. Android runtime. 5. Hardware Abstraction Layer (HAL). 6. Linux kernel. > [!note] > ![Android software stack](https://developer.android.com/static/guide/platform/images/android-stack_2x.png) # Linux kernel **What is the foundation of the Android platform?** The foundation of the Android platform is *the Linux kernel.* ...