Ubuntu is open source software. Simply put, open source software is software whose source code isn’t owned exclusively by any one person, group, or organization, but is instead made freely available for download. This makes Ubuntu different from proprietary software which requires users to purchase licenses before they are able to use the software on their computers. Microsoft Windows and Adobe Photoshop are examples of proprietary software.
Computer users can share and distribute open source software without fear of breaking intellectual property laws. They can also modify open source software to suit their individual needs, improve it, or translate it into other languages. Because open source software is developed by large communities of programmers distributed throughout the globe, it benefits from rapid development cycles and speedy security releases (in the event that someone discovers bugs in the software). In other words, open source software is updated, enhanced, and made more secure every day as programmers all over the world continue to improve it.
Aside from these technical advantages, open source software also has economic benefits. Most open source programs cost nothing to obtain or run.
Users needn’t purchase a license to run Ubuntu, for example.
To learn more about open source sofware, see the Open Source Initiative’s open source definition, available at http://www.opensource.org/docs/definition.php.