Android is a mobile operating system. It was originally created by a company called Android. In 2005, Google purchased Android for $50 million. It was a great move by Google. Right now Google is leading the mobile industry along with Apple.
The latest version of Android is called Lollipop and it was released on June 2014. To see the entire Android versions, go to the official Android page that contains more details about each version.
Since Android is being developed as an open source project, many companies are taking advantage of this and have developed their own version of Android. For example, Sony Ericsson and Motorola started developing their own mobile operating system but when Android started gaining momentum, they decided to use Android as their base for their new phones.
In later articles, I will cover in more detail the many features of Android 5 Lollipop.