Wikipedia offers a fairly comprehensive listing of many major sources of CC material across various domains.
First, remember that if your use of someone else’s CC licensed work falls under an exception or limitation to copyright (like fair use), then you have no obligations under the CC license.
When you find a CC work you want to reuse, the single most important thing to know is how to provide attribution. All CC licenses require that attribution be given to the creator.
The other main thing to consider during reuse is whether the creator as applied a NonCommercial license. If so, those licenses define noncommercial use as "not primarily intended for or directed towards commercial advantage or monetary compensation" (Creative Commons). The inclusion of “primarily” in the definition recognizes that no activity is completely disconnected from commercial activity; it is only the primary purpose of the reuse that needs to be evaluated as either commercial or noncommercial.
Combining and/or adapting CC-licensed works is a little more legally complicated than simply reusing them. Here are two important definitions to understand when using multiple CC-licensed works:
"Photo of 3 Orange Fruits" by Element5 Digital. Unsplash.
Whether creating an adaptation using one work or multiple works, you need to consider what options you have for licensing the copyright you have in your adaptation; this is called the Adapter’s License. Remember that your rights in your adaptation only apply to your own contributions. The original license continues to govern reuse of the elements from the original work that you used when creating your adaptation.
General rules for creating adaptations of CC licensed works:
CC License Compatibility Chart / CC BY 4.0
The License Compatibility Chart can help determine which licenses play nicely together, and which license to choose as an Adapters License. To use the chart, find a license that applies to one of the works on the left column and the license that applies to the other work on the top right row.
• If there is a check mark in the box where that row and column intersect, then the works under those two licenses can be remixed.
• If there is an “X” in the box, then the works may not be remixed unless an exception or limitation applies.
When using the chart, you can determine which license to use for your adaptation by choosing the more restrictive of the two licenses on the works you are combining. While that technically isn’t your only option for your adapter’s license, it is best practice because it eases reuse for downstream users.
CC Adapters License Chart / CC BY 4.0
You can use the Adapters License Chart to help you choose between available options for licensing your adaptation of a single CC-licensed work. When creating an adaptation of material under the license identified in the left hand column:
• You may license your contributions to the adaptation under one of the licenses indicated on the top row if the corresponding box is green.
• CC does not recommend using a license if the corresponding box is yellow, although doing so is technically permitted by the terms of the license. If you do, you should take additional care to mark the adaptation as involving multiple copyrights under different terms so that downstream users are aware of their obligations to comply with the licenses from all rights holders.
• Dark gray boxes indicate those licenses that you may not use as your adapter’s license.
• If the underlying work is licensed with BY or BY-NC, CC recommends your adapter’s license include at least the same license elements as the license applied to the original. For example, if you adapt a BY-NC work, you should apply BY-NC to your adaptation. If you adapt a BY work, they could apply either BY or BY-NC to your adaptation.
• If the underlying work is licensed with BY-SA or BY-NC-SA, your adapter’s license must be the same license applied to the original or a license that is designated as compatible with the original license (see compatibility chart above).
When you create a collection of CC works, you must still provide attribution and licensing information for each work. You also may have a separate copyright of your own that you may license. However, your copyright only extends to the new contributions you made to the work.
In the example below, Sam Winemiller owns the copyright for the slide deck itself and the elements of the slide deck he created. He licensed these original creations under CC-BY 4.0. Because he also included a collection of CC-licensed photos in this slide deck, he provided appropriate attribution for each, and is complying with any NonCommercial sharing restrictions applied by their creators. Remember: Collections are not considered adaptations, and if your reuse of a CC licensed work does not create an adaptation, then…
1. you are not required to apply a ShareAlike license to your overall work if you are using an SA-licensed work within it;
2. the NoDerivatives restriction does not prevent you from using an ND-licensed work; and
3. you can combine that CC-licensed material with other work as long as you attribute and comply with the NonCommercial restriction if it applies.
In addition to sources linked throughout the text, this guide drew information from "4.3 Finding and Reusing CC-Licensed Work" and "4.4 Remixing CC-Licensed Work" by Creative Commons. CC BY 4.0.