Works that would normally be protected under copyright law, or other intellectual property protections, can be made open through licensing. This includes:
Making your work open does not have to be an all-or-nothing decision. There are different permissions that you can pre-grant to others by making use of various licenses that communicate which rights you reserve and which rights you waive. Publishing your work through an open access journal or other open publisher often makes use of these types of licenses. It is important to note that once you apply a license to a work, you cannot remove it or revoke the permissions you've granted.
Copyright holders can automatically grant permission for others to use their works under certain conditions through such means as a Creative Commons (CC) license. Creative Commons helps authors share their knowledge and creativity more openly by ensuring that other users do not have to make fair use assessments or contact them for permission in many circumstances.
Creative Commons offers a Public Domain Mark and six licenses that make varying use of the following conditions:
BY 
– Credit must be given to the creator
NC 
– Only noncommercial uses of the work are permitted
SA 
– Adaptations must be shared under the same terms
ND 
– No derivatives or adaptations of the work are permitted
If you would like to apply a Creative Commons license to your work, simply use the Choose a License tool to help you select the right license for you, and mark your work with the license you've chosen. Creative Commons offers more considerations for using their licenses on their wiki.
In addition to Creative Commons, there are other options for applying a license to you work or communicating with potential users depending on your format or preferences.
GNU General Public License (GNU GPL) is a license that was developed for software, but it can be applied to some other types of works as well. GNU offers several other license types and also has documentation on the use and compatibility of other licenses.
Copyleft is a concept that describes "a strategy of utilizing copyright law and licensing to pursue the policy goal of fostering and encouraging the equal and inalienable right to copy, share, modify and improve creative works of authorship" and often carries with it the requirement to share derivative works alike. Copyleft is a play on "copyright" and may be used to describe a variety of licenses.
Konomark is not a license, but the mark communicates that an author is open to granting permission for use of their work and is an invitation to contact them regarding your desired use.
Publishing your research in open access journals is a good way to increase the openness of your scholarship. Learn more on our Open Access guide or visit the Directory of Open Access Journals to identify titles in your field.
Scholars have created many open textbooks, lesson plans, supplemental materials, courses, and more that can be used in teaching. To find out more about these resources, visit the Open Educational Resources guide.
Open Door Vectors by Vecteezy
Creative Commons License Spectrum by Shaddim is licensed under the Creative Commons Attribution 4.0 International license