SLIDE GIVES EXPLANATION ABOUT VARIOUS OS

1. OS STRUCTURE

3. APPLICATION PROGRAM
Application programs are used to perform
specific tasks for users. Application software
runs on top of system software.
(Ex) Ms-word, Ms-excel, powerpoint, access etc.

4. SYSTEM PROGRAM
System programs are computer programs that
provide platform for application programs to
work.
Without the system software also called
operating system, the computer system cannot
work.
(Ex) Any OS

5. DEFINITION
A device driver is a small piece of software that
tells the operating system and other software
how to communicate with a piece of hardware.
Without drivers, the computer would not be
able to send and receive data correctly to
hardware devices, such as a printer.
.

7. EXAMPLE OF DEVICE DRIVERS
(Ex) Printer drivers tell the operating system,
and by extension whatever program you have
the thing you want to print open in, exactly how
to print information on the page.

9. ANDROID OS

10. ANDROID
Android is a Linux-based operating system designed
primarily for touchscreen mobile devices such as
smartphones and tablets.
The first Android-powered phone was sold in October
2008.

11. FEATURES OF ANDROID
User gets millions of applications that user can not
get in any other mobile operating system. (Google
Play Store).
Android supports advanced audio/video/still media
formats such as MPEG-4, H.264, MP3, and AAC, AMR,
JPEG, PNG, GIF.

12. It has several Pre – Installed applications like Gmail,
Maps etc.
It provides RDBMS SQLITE for data storage and
data sharing for various applications.
No need to get permission from Third party
developers

13. STRUCTURE OF ANDROID OS

15. APPLICATION FRAMEWORK
It is used to implement a standard structure for
different applications. So that programmer can
make easy use of it.
Notifications Manager − Allows applications to
display alerts and notifications to the user.
Resource Manager − Provides access to color
settings and user interface layouts.
Activity Manager − Controls all aspects of the
application lifecycle and activity stack.

16. LIBRARIES
android.widget − A rich collection of pre-built
user interface components such as buttons,
labels, list views, layout managers, radio buttons
etc.
android.os − Provides applications with access
to standard operating system

17. LIBRARIES
android.database − Used to access data
published by content providers and includes
SQLite database management classes

18. RUNTIME
A key component called Dalvik Virtual
Machine which is a kind of Java Virtual Machine
specially designed and optimized for Android.
Dalvik translates a Java program into machine
code of mobile device.

19. KERNEL
It is the heart of android architecture that exists
at the root of android architecture.
Linux kernel is responsible for device drivers,
power management, memory management,
device management and resource access.

20. iOS

21. Market share
Market Share 2015
Second mobile OS in usage
First mobile OS in revenue

22. ABOUT IOS
iOS (originally iPhone OS) is a mobile operating
system created and developed by Apple. It is the
second most popular mobile operating system in
the world by sales, after Android.

23. iOS STRUCTURE

24. COCOA TOUCH LAYER
The Cocoa Touch layer define the appearance of
your app.
They also provide the basic app infrastructure
and support for key technologies such as
multitasking, touch-based input, push
notifications

25. MEDIA LAYER
The Media layer contains the graphics, audio,
and video technologies you use to implement
multimedia experiences in your apps.

26. CORE SERVICES LAYER
The Core Services layer contains fundamental
system services for apps
Features such as location, iCloud, social media,
and networking.

27. CORE OS LAYER
• File-system access
• Standard I/O
• Memory allocation