Creative Commons Attribution NonCommercial ShareAlike
What is a "licence"?
The word "licence" literally means "permission". When someone obtains a licence, they receive a set of permissions set down in the written text of the licence. If software is released "under a licence", it means that it is released together with permissions regarding its use. Permissions are typically granted with conditions attached.
You can't give anyone permission to use something which you don't own. In other words, only the copyright-holder can grant a licence. The copyright-holder is usually the person identified as the author.
Typically a licence will state, among other things:
- who owns the copyright, which is usually the same as the person granting the permissions.
- what the permissions are.
Explanation of the abbreviation CC-BY-NC-SA
The abbreviations are widely known in the open licencing world. The BY-NC-SA part describes three crucial conditions attached to the permission to use the software or media freely.
- CC = Creative Commons
- BY = you always have to say who the module is "by" (authorship, attribution) [condition 1]
- NC = non-commercial [condition 2]
- SA = share-alike (i.e. derivative works must use the same licence) [condition 3]
The CC bit is just used to help identify what kind of licence it is. Sometimes the CC is dropped, as it is not a condition.
Rough explanation of meaning
- Can anyone use and play the module free-of-charge? Yes
- Can anyone sell or make money from the module? No
- Can anyone redistribute the module from their own website? Yes
- Can anyone redistribute the module on a free CD-ROM compilation of learning materials? Yes
- Can anyone modify, extend or correct the module? Yes, but only if they use the same CC-BY-NC-SA licence for the result.
- Can anyone pass off the module as their own work? No, they must acknowledge the original author.
- Who owns the copyright? The author does. This is not public domain licencing.
- Can I, as author, change my mind about publication? No. The permissions you have granted cannot be revoked.