Creative Commons (CC) is a public copyright license. What does this mean? It means it allows for free distribution of work that would otherwise be under copyright, providing open access to users. Creative Commons licensing provides both gratis OA licensing and libre OA licensing (terms coined by Peter Suber). Gratis OA is free to use, libre OA is free to use and free to modify.
How does CC licensing benefit the artist? Well, it allows more flexibility with what they can allow others to do with their work. How does it benefit the user? As a user, you are protected from copyright infringement, as long as you follow the CC license conditions.
CC licenses: in a nutshell with examples
BY – attribution | SA – share alike | NC – non-commercial | ND – no derivs
CC0 – creative commons zero license means this work is in the public domain and you can do whatever you want with it. No attribution is required. This is the easiest license to work with. (example of a CC0 license: Unsplash)
BY – This license means that you can do as you wish with the work but only as long as you provide attribution for the original creator. Works with this type of license can be expanded on and used for commercial use, if the user wishes, as long as attribution is given to the original creator. (example of a CC-BY license: Figshare ; data sets at Figshare are CC0; PLOS)
BY-SA – This license is an attribution licenses and share alike license meaning that all new works based on the original work will carry the same license. (example of a CC-BY-SA license: Arduino)
BY-NC – this license is another attribution license but the user does not have to retain the same licensing terms as the original work. The catch, the user must be using the work non-commercially. (example of a BY-NC license: Ely Ivy from the Free Music Archive)
BY-ND – This license means the work can be shared, commercially or non-commercially, but without change to the original work and attribution/credit must be given. (example of a BY-ND license: Free Software Foundation)
BY-NC-SA – This license combines the share alike and the non-commercial with an attribution requirement. Meaning, the work can be used (with attribution/credit) only if for non-commercial use and any and all new works retain the same BY-NC-SA license. (example of a CC BY-NC-SA: Nursing Clio see footer or MITOpenCourseWare)
BY-NC-ND – This license combines the non-commercial and non-derivative licenses with an attribution requirement. Meaning, you can only use works with this license with attribution/credit for non-commercial use and they cannot be changed from the original work. (example of a BY-NC-ND license: Ted Talk Videos)