TYPES OF OPERATING SYSTEM• CUPCAKE (1.5) • DONUT (1.6)• ECLAIR(2.0,2.1)• FROYO (2.2,2.2.3)• GINGERBREAD (2.3.2.3.7)• HONEYCOMB (3.0,3.2.6)
• ICE CREAM SANDWICH (4.0.4.0.4)• JELLY BEAN (4.1 , 4.3.1 )• KITKAT ( 4.4 , 4.4.4, 4.4W, 4.4W.2)• LOLLIPOP ( 5.0 , 5.1.1)• MARSHMALLOW ( 6.0)
OHA (OPEN HANDSET ALLIANCE)
o A business alliance consisting of 47 companies to develop open standards for mobile devices
OPERATING SYSTEM• An operating system (OS) is system software that manages computer hardware and
software resources and provides common services for computer programs. The operating system is a component of the system software in a computer system. Application programs usually require an operating system to function. Time-sharing operating systems schedule tasks for efficient use of the system and may also include accounting software for cost allocation of processor time, mass storage, printing, and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware,[1][2] although the application code is usually executed directly by the hardware and frequently makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computer—from cellular phones and video game consoles to web servers and supercomputers.
EXAMPLES • Examples of popular modern operating systems include
BlackBerry, BSD, iOS, Linux (Android, Chrome OS, Debian, Fedora, Gentoo, PCLinuxOS, RHEL ), OS X, QNX,Steam OS, Microsoft Windows (and variant Windows Phone),[3] and z/OS. The first seven of these examples share roots in Unix. Popular hard real-time operating systems include FreeRTOS, Micrium and VxWorks
WHAT IS AN ANDROID Android is a
software stack for mobile devices that includes an operating system, middleware and key applications.
TABLETSVelocity Micro Cruz
Game FlyTouchAcer beTouch
Dawa D7
Toshiba Android SmartBook
Cisco Android Tablet
Android S/W Stack - Application
Android provides a set of core applications: Email Client SMS Program Calendar Maps Browser Contacts Etc
All applications are written using the Java language.
Android S/W Stack - Libraries
Including a set of C/C++ libraries used by components of the Android system
Exposed to developers through the Android application framework
Android S/W Stack - Runtime
Core Libraries Providing most of the functionality available in
the core libraries of the Java language APIs
Data Structures Utilities File Access Network Access Graphics Etc
Android S/W Stack – Runtime (Cont) Dalvik Virtual Machine
Providing environment on which every Android application runs
Each Android application runs in its own process, with its own instance of the Dalvik VM.
Dalvik has been written such that a device can run multiple VMs efficiently.
Register-based virtual machine
Android S/W Stack – Runtime (Cont) Dalvik Virtual Machine (Cont)
Executing the Dalvik Executable (.dex) format .dex format is optimized for minimal memory
footprint. Compilation
Relying on the Linux Kernel for: Threading Low-level memory management
Android S/W Stack – Linux Kernel
Relying on Linux Kernel 2.6 for core system services Memory and Process Management Network Stack Driver Model Security
Providing an abstraction layer between the H/W and the rest of the S/W stack