Google Android is a Linux mobile OS

Google Android is a Linux mobile OS ..

Android is Google’s open source mobile phone operating system that runs on devices like the T-Mobile G1, Motorola Droid, and Google Nexus One. Because of the nature of open-source, it is possible to port Android to entirely new devices without the approval or assistance of official parties. As such, there is an effort to port Android to a variety of Windows Mobile smart-phones.

Linux is a generic term referring to Unix-like computer operating systems based on the Linux kernel. Their development is one of the most prominent examples of free and open source software collaboration; typically all the underlying source code can be used, freely modified, and redistributed, both commercially and non-commercially, by anyone under licenses such as the GNU General Public License.Linux can be installed on a wide variety of computer hardware, ranging from embedded devices such as mobile phones, smart-phones and wristwatches to mainframes and supercomputers. Linux is predominantly known for its use in servers; in 2007 Linux's overall share of the server market was estimated at 12.7%, while a 2008 estimate suggested that 60% of all web servers ran Linux.if you are interested to read about Linux for mobiles and smart phones ...see this

http://www.handhelds.org/moin/moin.cgi/UniversalHowtoInstallLinux



Android enables the developers to write managed code in the Java language, controlling the device via Google-developed Java libraries.the most interesting thing that Google released most of the Android code under the Apache License, a free software and open source license.

Also Android can run the native codes. Libraries written in C and other languages can be compiled to ARM native code and installed using the Android Native Development Kit. Native classes can be called from Java code running under the Dalvik VM using the System.loadLibrary call, which is part of the standard Android Java classes.

Complete applications can be compiled and installed using traditional development tools. The ADB debugger gives a root shell under the Android Emulator which allows native ARM code to be uploaded and executed. ARM code can be compiled using GCC on a standard PC. Running native code is complicated by the fact that Android uses a non-standard C library (known as Bionic). The underlying graphics device is available as a framebuffer at /dev/graphics/fb0. The graphics library that Android uses to arbitrate and control access to this device is called the Skia Graphics Library (SGL), and it has been released under an open source license. Skia has backends for both win32 and Cairo, allowing the development of cross-platform applications, and it is the graphics engine underlying the Google Chrome web browser.

Hardware running Android

• Cellular networking : GSM, EDGE, 3G (hardware dependent).
• LAN : Bluetooth, and Wi-Fi (hardware dependent).
• Graphics Hardware Acceleration.
• Camera, GPS and Compass (hardware dependent).
• Touch screen and accelerometer for motion sensing.

Android Software features

• Integrated browser based on the open source WebKit  engine.

• SQLite for relational data storage.

• Media support for common audio, video, and still image formats(MPEG4 , H.264, MP3, AAC, AMR, JPG, PNG, GIF).

• Dalvik Virtual Machine optimized for mobile devices.

Current features and specifications 2.1:

Handset layouts	The platform is adaptable to larger, VGA, 2D graphics library, 3D graphics library based on OpenGL ES 2.0 specifications, and traditional smartphone layouts.
Storage	The Database Software SQLite is used for data storage purposes
Connectivity	Android supports connectivity technologies including GSM/EDGE, IDEN, CDMA,EV-DO, UMTS, Bluetooth, Wi-Fi, and WiMAX.
Messaging	SMS and MMS are available forms of messaging including threaded text messaging.
Web browser	The web browser available in Android is based on the open-source WebKitapplication framework. The browser scores a 93/100 on the Acid3 Test.
Java support	Software written in Java can be compiled to be executed in the Dalvik virtual machine, which is a specialized VM implementation designed for mobile device use, although not technically a standard Java Virtual Machine. Android does not supportJ2ME, like some other mobile operating systems.
Media support	Android supports the following audio/video/still media formats: H.263, H.264 (in 3GPor MP4 container), MPEG-4 SP, AMR, AMR-WB (in 3GP container), AAC, HE-AAC(in MP4 or 3GP container), MP3, MIDI, Ogg Vorbis, WAV, JPEG, PNG, GIF,BMP.[51]
Additional hardware supportorientation	Android can use video/still cameras, touchscreens, GPS, accelerometers,magnetometers, accelerated 2D bit blits (with hardware , scaling, pixel format conversion) and accelerated 3D graphics.
Development environment	Includes a device emulator, tools for debugging, memory and performance profiling, and a plugin for the Eclipse IDE.
Market	Like many phone-based application stores, the Android Market is a catalog of applications that can be downloaded and installed to target hardware over-the-air, without the use of a PC. Originally only free applications were supported. Paid-for applications have been available on the Android Market in the United States since 19 February 2009.[52] The Android Market has been expanding rapidly. As of April 30, 2010, it had over 50,000 Android applications for download.[53]
Multi-touch	Android has native support for multi-touch which was initially made available in handsets such as the HTC Hero. The feature was initially disabled at the kernel level (possibly to avoid infringing Apple's patents on touch-screen technology[54]). Google has since released an update for the Nexus One and the Motorola Droid which enables multi-touch natively.[55]
Bluetooth	Support for sending files over bluetooth was added in version 2.0.
Videocalling	Android does not support videocalling. However, it is possible if the phone runs an additional UI. This is proved on the HTC Evo 4G, which runs Sense and can support videocalling.[citation needed]

Application Framework

• Content providers: Enable applications  access data from other applications ,sharing.
• Resource Manager :Providing access to non-code resources.
• Notification Manager :Enables all applications to display  alerts in the status bar.
• Activity Manager :Manages the life cycle of applications.

Linux Kernel

• Linux Version 2.6.
• Security, Memory & Process Management.
• Proven driver model.
• Efficient computing resource management.
• Stable and proven OS for mobile platform.

Yours Moataz Muhammed