License:CC-BY-SA

Old style marking of a CC-BY-SA license:   

New style badge of a CC-BY-SA license:

To learn about CC-BY-SA as part of the Creative Commons licenses suite, see English Wikipedia

CC-BY-SA enhances the CC-BY license which claims that the creator(s) of a cultural work aka the licensor(s) shall be named as such in any shared copy or shared recording or actual public performance of the work, for any new variant of it. That's the meaning of the BY-clause. The SA-clause aka ShareAlike clause means that any sharing of the work or variants of it MUST be licensed in the same way as the CC-BY-SA does. Therefore You must know:

Only the early license version 1.0 of CC-BY-SA obliges to share the work or variants of it also under CC-BY-SA 1.0. Of course that first license version is completely outdated because it's designed just for the USA.

The version 4.0 of the CC-BY-SA license is, according to creativecommons.org, upward compatible with the CC-BY-SA license versions 2.0, 2.5 and 3.0 !

If any new cultural work in this wiki is designated as CC-BY-SA licensed w/o version number, we and any user of the wiki must suppose that this means at least CC-BY-SA version 2.0. This assumption allows to create variants to be shared in the license variants 2.5, 3.0 or 4.0 since they are officially declared upward compatible to version 2.0 by creativecommons.org

If a work is licensed CC-BY-SA in one of the versions 2.0, 2.5 or 3.0, then you can create variants licensed CC-BY-SA in the same or any higher numbered version!

If You are not the creator aka licensor of a free work that you publish in this wiki, but that work had the CC-BY-SA license version 1.0, then and only the you must share it here under that outdated license version and none other.