Open access is a movement to make research works such as articles, data, software, etc., available freely, immediately, and permanently online to the public without financial and technical barriers. Researchers may be mandated by funders or institutions to make their work open access. While open access works are free to view, they may not be free to reuse depending on their license. Creative Commons and Public Domain licenses are the most commonly attached to open access works. There are two ways that researchers can make their works open access, through green open access or gold open access. Through green open access, researchers deposit and make their works freely accessible through an online repository or website. Through gold open access, researchers pay a journal to make their work open access.