General Information

Help and Support
News and Media
Why It's Free
Contact Us

South African Projects
     Education Project
     Marketing Project

Please support our Sponsors.

Why It's Free is made available under two combined licences, the LGPL (Lesser GNU Public Licence) and the SISSL (Sun Industry Standards Source Licence). Project documentation is made available under the PDL (Public Document Licence) Licence.

The basic result of the licences is that the source code of must be made freely available to all users of the suite and that the users may, in turn, freely distribute the source. Whilst this does not make the program explicitly available in useable format at no charge, the practical effect is to do so.

Why Different Licences?

Dual licencing of the source code provides open and free access to the technology both for the GPL community and for other developers or companies that cannot use the GPL. Dual licencing is common practice in open-source projects like Perl and Mozilla. Through the combined use of the LGPL and SISSL, developers have a high degree of freedom with compatibility and interoperability being preserved. For more information see the white paper from Sun at

Effect of the Licences

The basic effect of the licences are that you can freely modify, extend and improve the source code. The only question is whether or not you must provide the source code and contribute modifications to the community. The GPL and SISSL licenses allow different ranges of flexibility in this regard, but in the end, regardless of the license used, any and all incompatible changes must be published openly.

Why Use LGPL?

The LGPL has all of the restrictions and freedoms of the GPL except that you may use the code at compile-time without the derivative work becoming a GPL work. This allows the use of the code in non-free works.

Why Use SISSL?

The SISSL licence allows the user to do what they like with the source, modify it, extend it, etc., but the licencee must maintain compatibility. Attachment A of the SISSL defines the standards that must be met to comply with the licence. For, the standards identified are the LGPL versions of the technology language-independent APIs and XML-based file formats. If these standards are broken, the licencee must provide a reference implementation of sources which constitute the modification, thereby opening the details of any incompatibility/modification which may have been introduced.

Can Sun ever take away the code?

The simple answer to this is NO. Once code is released under the LGPL, it can never be taken away. Sun is subject to the same rules as the rest of the community, including giving back modifications under the LGPL (or a specification and reference implementation under the terms of the SISSL). Thus, Sun can never take away the code and the community's contributions to it. This code belongs to the community as guaranteed by the LGPL and the SISSL.

Developed and Maintained by
All products, services, companies, events publications and names are trademarks, registered trademarks, copyrights or service marks of their respective owners. Hosting Sponsored by