Sharing, adaptation and attribution
Attribution-ShareAlike 4.0 International allows copying, redistribution, remixing and adaptation, including commercial uses. Attribution, a licence link and identification of changes remain requirements.
ShareAlike adds conditions for shared adaptations so later recipients can continue to use them under the prescribed licensing arrangements, rather than receiving only a one-off permission.
Adaptation differs from aggregation
The scope depends first on whether an adaptation exists under copyright law. Creative Commons identifies translation as an example; merely including an unchanged work alongside unrelated material does not automatically make the whole collection an adaptation.
Linking to or discussing a work also differs from distributing adapted material. Applicable law can affect the classification, so sharing a webpage, course or directory is not by itself a universal test.
References: [2]
Compatibility and continuing reuse
Licensing a shared adaptation must follow the ShareAlike rules. Compatibility is not established merely because two licences sound similarly open; Creative Commons names compatible arrangements through its process.
Extra terms or technological restrictions may not block permitted acts. ShareAlike does not require publication of every private adaptation, nor does it remove statutory exceptions. Version, action and the material concerned all matter to its operation.