OPERANTING SYSTEM -OS

Operating systems provide a software platform on top of which other programs, called application programs, can run. The application programs must be written to run on top of a particular operating system. Your choice of operating system, therefore, determines to a great extent the applications you can run. For PCs, the most popular operating systems are DOS, OS/2, and Windows, but others are available, such as Linux.

The three most popular types of operating systems for personal and business computing include Linux, Windows and Mac

Windows

is a family of operating systems for personal and business computers.

Mac

OS is the official name of the Apple Macintosh operating system.

Linux

Linux is a freely distributed open source operating system that runs on a number of hardware platforms

Multi-user

Allows two or more users to run programs at the same time. Some operating systems permit hundreds or even thousands of concurrent users.

Multiprocessing

Supports running a program on more than one CPU

Multitasking

Allows more than one program to run concurrently

Multithreading

Allows different parts of a single program to run concurrently

• Real time

Responds to input instantly. General-purpose operating systems, such as DOS and UNIX, are not real-time.

1. Android OS (Google Inc.)

2. Bada (Samsung Electronics)

3. BlackBerry OS (Research In Motion)

4. iPhone OS / iOS (Apple)

5. MeeGo OS (Nokia and Intel)

6. Palm OS (Garnet OS)

7. Symbian OS (Nokia)

8. webOS (Palm/HP)

9. Windows Mobile (Windows Phone)