What is Android ?

Android :

Android Inc. founded in Palo Alto, california ,united states in October 2003 by Andy Rubin,rich miner, nick sears and Chris white to develop.

In 17th August 2005, Google acquired android Incorporation. Since then, it is in the subsidiary of Google Incorporation.

It is a open source software platform and operating system for
mobile devices and based on the Linux kernel. Android was developed by Google and the Open Handset Alliance (OHA), a coalition of hardware, software and telecommunications companies.

Different Android versions, released date and their name :

Android version 1.0 (Alpha) released on September 23, 2008.
Android version 1.1 (Beta) released on February 9, 2009.
Android version 1.5 (Cupcake) released on April 27,2009.
Android version 1.6 (Donut) released on September 15, 2009.
Android version 2.0 released (Eclair) on October 29, 2009.
Android version 2.1 released on January 12, 2010.
Android version 2.2 (Froyo) released on May 20, 2010.
Android version 2.3 (Gingerbread) released on December 6, 2010.
Android version 3.0 (Honeycomb) released on February 22, 2011.
Android version 3.1 released on May 10, 2011.
Android version 3.2 released on July 15, 2011.
Android version 4.0 (Ice Cream Sandwich) released on October 8, 2011.
Android version 4.1 (Jelly Bean) released on July 9, 2012.
Android version 4.2 released on November 13, 2012.
Android version 4.3 released on July 24, 2013.
Android version 4.4 (KitKat) released on October 31, 2013.
Android version 5.0 (Lollipop) released on November 3, 2014.
Android version 6.0 (Marshmallow) released on October 5, 2015.
Android version 7.0 (Nougat) released on August 22, 2016.
Android version 8.0 (Oreo) released on August 21, 2017.
Android version 9.0 (Pie) released on  August 6, 2018.

For more details : What is Android ?