MEDLINE is the largest component of PubMed and consists primarily of citations from journals selected for MEDLINE; articles indexed with MeSH (Medical Subject Headings) and curated with funding, genetic, chemical and other metadata.
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books.
It does not include full-text journal articles; however, links to the full text are often present when available from other sources, such as the publisher's website or PubMed Central (PMC).
Citations in PubMed primarily stem from the biomedicine and health fields, and related disciplines such as life sciences, behavioral sciences, chemical sciences, and bioengineering.
Available to the public online since 1996, PubMed was developed and is maintained by the National Center for Biotechnology Information (NCBI), at the U.S. National Library of Medicine (NLM), located at the National Institutes of Health (NIH).