Copyright protection attaches automatically to original works you create, whether a poem, photograph, painting, song, video, or essay. Copyright limits what others can do with your creative work and protects your original work from, for example, being compiled or reused and sold for profit. If you hold the copyright—and didn’t, say, create the original work in an employment context where it may be subject to being a work for hire—you may want to allow others to use your work for particular purposes. You could individually negotiate a license granting rights to each person, which would undoubtedly take more and more time as licensing requests mount, or you could use a Creative Commons license to manage your intellectual property in an all-encompassing manner.
Brown, Kincaid C. "Creative Commons: An Explainer." Mich. B. J. 97, no. 9 (2018): 52-3.