Android is an open-source and Linux-kernel based operating system that is optimized for tablet computers, mobile devices, televisions etc.
It is a computer software stack for mobile devices that attach middleware, operating system, and key applications.
It is developed by Andy Rubin and Rich Miner, in 2015. And later Android Inc. was acquired by Google.
To write an Android Code, Mainly used a Java language, even through different language can be used. Actually, the Android OS is mainly used for smart phones and mobiles.