Android is a mobile operating system that uses a custom Linux kernel. You can imagine a kernel as the brain of an operating system. The type of kernel used in an OS determines what type of OS it is. Linux flavors use a Linux kernel, Windows editions use the Windows NT kernel, iOS and macOS use Apple's XNU kernel (XNU itself is based on Unix). Easy right?
Android is a mobile operating system based on a modified version of the Linux kernel and other open source software, designed primarily for touchscreen mobile devices such as smartphones and tablets Android is developed by a consortium of developers known as the Open Handset Alliance and commercially sponsored by Google It was unveiled in 2007, with the first commercial Android device launched in September 2008 It is free and open source software its source code is known as Android Open Source Project (AOSP) which is primarily licensed under the Apache License However most Android devices ship with additional proprietary software pre-installed, most notably Google Mobile Services (GMS) which includes core apps such as Google Chrome, the digital distribution platform Google Play and associated Google Play Services development platform