This document provides a history of the Android operating system and its various versions from its inception in 2003 to the present. It describes how Android was originally developed by Android Inc. and is now maintained by Google. It then summarizes each major version of Android, highlighting new features and capabilities. The versions discussed include 1.1, 1.5 Cupcake, 1.6 Donut, 2.0-2.1 Eclair, 2.2 Froyo, 2.3-2.3.7 Gingerbread, 3.0-3.2 Honeycomb, 4.0-4.0.4 Ice Cream Sandwich, 4.1-4.3 JellyBean, and 5.0