Sharealike: Difference between revisions

'''Share-alike''' is a required reintegration clause of several [[parametric license]]s in [[Creative Commons]] and some monolithic ones like [[GFDL]].  It simply means that anyone improving a work must share the improved work with others who wish to use or improve it.   

It is a key feature of the [[GPL]] too which applies this principle to [[source code]].  It is sometimes called the '''viral license''' feature - the fact that accepting the license breeds more acceptance of the license.  This is considered very desirable by some and very undesirable by others (who started the [[open source]] movement to oppose the '''share-alike''' requirement.  ''See also [[problems with free software and open source models]].''

The most common '''share-alike''' licenses used are in '''open content''' and in '''free documentation''' efforts, which require such licenses by definition:

 

 

*the [[CC-by-sa]] license, quite close to the [[GFDL]] but is incompatible with it.  ''Things licensed under the CC regime are not part of the [[GFDL Corpus]].'' This license is used at [[Wikitravel]]

 

Most efforts use share alike licenses for both code and content, e.g. the '''CC-nc-sa''' license - the closest approximation yet to a [[Green Documentation License]] - is used for [[GetWiki]] code.