Abstract Introduction Open source refers to software that's free to the public. More specifically, the software's source code is available to the public to use and/or modify. You can use the program as is or modify its source code to suit your needs, without fear of legal reprisals. If your commercial software has a bug, you have to wait for a patch or upgrade, if the company even decides to fix it. If open source software has a bug, developers in the community fix it as quickly as they discover it.  They then redistribute their modifications -- and it all happens much quicker than in a commercial product. Examples of open source software are android, Linux, fedora, Ubuntu, red hat, Firefox, apache, open office, etc. Android is the latest trend that is emerging into powerful technology which is an open source. It is on phones of tiny size to tablet model. This concept concludes that Developers programming under Open Source can be confident that what they are producing will contribute positively for the greatest number of society. All members, whether programming, working on documentation, or simply using an application, are seen as contributing to the greater good. It's a breath of fresh air, and a fun place to be. I. Applicationd Some of the applications are GNU/LINUX, Android, Mozilla Firefox, and Apache HTTP Server. II. Function Making open source software can be more profitable in long term. The open source inventions of today are aimed at solving specific problems that businesses are facing, especially those resulting from the web. III. Advantages Very fast fixes for bugs and security exploits, with very fast upgrades to new releases Multiple options for software for any given task Multiple support streams, though this can be a drawback as well A lower cost to obtain, since it is usually free Feature implementation is faster IV. Conclusion In the current scenario it’s important to mention that an immediate switch from pr