Link to Resource Connect to Resource PubMed is a free, online index for biomedical and related literature. It is primarily composed of the citations in MEDLINE, but includes additional content including materials not yet in MEDLINE, and material hosted on PubMed Central. There is a basic search as well as a comprehensive advanced search, which includes the standard search fields but also includes more rare pieces of information such as grant number, MeSH terms, and pharmacological action. MeSH, or Medical Subject Headings, are biomedically specific, and consistently applied subject terms for the books and journal articles in MEDLINE and elsewhere. The mobile version of PubMed, PubMed Mobile, is available.