Researchers are often unsure about open access copyright permissions for their journal article, preprint or thesis. What open access rights do you retain when signing the publisher agreement for a journal article? Are you permitted to self-archive in your institutional repository? Which Creative Commons licence to select for your preprint? Your choices affect what you and others can do with your work. This introduction deciphers the jargon and explains the pitfalls so you can understand your options and make informed decisions.