PubMed comprises over 30 million citations for biomedical literature from MEDLINE, life science journals, and online books, citations and abstracts dating back to 1966, selectively to 1865, and very selectively to 1809. PubMed is the world's largest database of biomedical and health sciences literature.
- PubMed launched in 1996, is the interface used to access Medline, PubMed Central, plus additional materials (preprints, pre 1966 citations not yet updated to Medline, NCBI bookshelf, etc.). The earliest literature in PubMed dates back to the early 1800's.
- The name PubMed means for Public access to Medline.
- MEDLINE is the National Library of Medicine (NLM) journal citation database; previously MEDLARS which launched in 1964.
- PubMed Central launched in 2000 as a free archive for full-text biomedical and life sciences journal articles.
- MeSH, or Medical Subject Headings, are the National Library of Medicine's controlled vocabulary for indexing articles for MEDLINE/PubMed. Searching by using MeSH provide a consistent way to retrieve information that may use different terminology for the same concepts; locate MeSH using the MeSH database.