Android is an open source operating system based on Linux that was developed by Google. It aims to provide a rich experience for mobile users. The Android platform is the product of the Open Handset Alliance led by Google to build better mobile phones. The Android SDK contains tools and documentation to help developers build Android applications, including the Android emulator to test apps without a physical device. Key benefits are the open platform and free licensing, while challenges include performance and vendor integration. Market response will be a key factor.