1, OA journal (open access journal articles): refers to academic journal articles obtained free of charge on the Internet, and the quality is guaranteed after peer review and academic editor review. It can be obtained through major academic databases, academic search engines and academic social platforms.
2.OA books: refer to electronic books that can be obtained free of charge, covering various disciplines, including textbooks, academic monographs, popular science books, etc. It can be obtained through the websites of major online libraries, digital libraries and academic institutions.
3.OA courses: refers to open access online courses, including university courses and online courses, which can be obtained through major online learning platforms and websites of educational institutions.
4.OA patents and standards: refers to the open access to patent documents and standard documents, which can be obtained through relevant websites and patent office websites.