Open Source

   
Home: Software Licenses

Articles

Copyright Issues
Open Source & Derivative Works

GPL Issues
GPL Validity
GPL Violations
WordPress & the GPL

Legal Cases
ProCD v. Zeidenberg
USL v. BSDi

Glossary

Advertising Clause
Click-Through License
Compatible Licenses
Copyleft
Derivative Works
Dual Licensing
EULA
FLOSS
FOSS
Free Software
Incompatible Licenses
OSD
OSI Certified
OSS
Permissive Licenses
Shrink Wrap License
Viral Licenses

Open Source

Licenses
   AGPL
   Apache
   Apple
   Artistic
   BSD
   CDDL
   CPL
   EPL
   GPL v2
   GPL v3
   IPL
   LGPL
   MIT
   Mozilla
   SPL
   X License
   X11 License

Organizations
   ASF
   FSF
   OSI
   SFLC

People
   Bruce Perens
   Eben Moglen
   Eric Raymond
   Lawrence Lessig
   Linus Torvalds
   Richard Stallman

Proprietary Licenses

Licenses
   Closed Source
   Freeware
   Shareware

Organizations
   BSA

Shared Source Licenses

MS Community License
MS Permissive License

Uncopyrighted

Public Domain

Further Reading

Books




 
 














































 
Software Licenses   >   Open Source

   
 

Open Source


Open Source Software ("OSS") is computer software for which the source code is made available, and for which it is usually (some exceptions, rules and restrictions may apply) permitted to study, modify and improve the software. Additionally, users are also normally permitted (again, exceptions, rules and restrictions may apply) to distribute the software in modified or unmodified form.

Open Source is not a trademark, so while most people used the term in broadly the same way, sometimes you may find that software described as "Open Source" is actually being distributed on a different licensing basis, etc. To reduce the possibility of confusion, the Open Source Initiative developed a set of 10 criteria (OSD) for Open Source licenses, and those licenses which have been verified as satisfying those critera may be described as OSI Certified.

Closely related to Open Source is Free Software, as defined by the Free Software Foundation. Free Software is software that is licensed so as to provide the following four freedoms (numbered from zero), and for which access to the source code is considered a precondition (in particular a precondition for freedoms 1 and 3):
  1. To run the program, for any purpose
  2. To study how the program works, and to adapt it for your needs
  3. To redistribute copies
  4. To improve the program and to release your improvements to the public
In practical terms, most Open Source Software may also be considered Free Software and vice-versa, hence they are often placed together in a combined category named either Free/Open-Source Software ("FOSS") or Free/Libre/Open-Source Software ("FLOSS").

An important point to note about both Open Source and Free Software is that with the exception of public domain software (which is sometimes classified as a subtype of Open Source or Free Software), the software is copyrighted, there are terms and conditions which apply, and that using or distributing the software in violation of the terms and conditions is almost certainly copyright infringement.

The information in the Open Source section of this web site includes:
  • Licenses
    Information about Free and Open-Source software licenses.

  • Organizations
    Information about key organizations involved with Free and Open-Source software.

  • People
    Information about people who have contributed to Free and Open-Source software.
Related Links Related Pages
   
Discuss Open Source
Please feel free to post your comments:

Facebook Comments: