Open source
Open source or open-source is the idea that source code for a piece of software is freely available for viewing and modifying. According to the Open Source Definition, the following ten conditions must be met to be considered "open source":
- Free Redistribution: the software can be freely given away or sold. (This was intended to expand sharing and use of the software on a legal basis.)
- Source Code: the source code must either be included or freely obtainable. (Without source code, making changes or modifications can be impossible.)
- Derived Works: redistribution of modifications must be allowed. (To allow legal sharing and to permit new features or repairs.)
- Integrity of The Author's Source Code: licenses may require that modifications are redistributed only as patches.
- No Discrimination Against Persons or Groups: no one can be locked out.
- No Discrimination Against Fields of Endeavor: commercial users cannot be excluded.
- Distribution of License: The rights attached to the program must apply to all to whom the program is redistributed without the need for execution of an additional license by those parties.
- License Must Not Be Specific to a Product: the program cannot be licensed only as part of a larger distribution.
- License Must Not Restrict Other Software: the license cannot insist that any other software it is distributed with must also be open source.
- License Must Be Technology-Neutral: no click-wrap licenses or other medium-specific ways of accepting the license must be required.
The MIT/X11 License is an example of an open source license.