This How PubMed Works: Medical Subject Headings session addresses increasing health information access and use by highlighting features of the National Library of Medicine’s PubMed bibliographic database. The Medical Subject Headings (MeSH) thesaurus is a controlled and hierarchically-organized vocabulary produced by the National Library of Medicine. It is used for indexing, cataloging, and searching of biomedical and health-related information. MeSH includes the subject headings appearing in MEDLINE/PubMed, the NLM Catalog, and other NLM databases. By registering for this class, you are agreeing to the NNLM Code of Conduct Objectives: Investigate the MeSH DatabaseDescribe a Controlled VocabularySummarize the four types of MeSH TermsExplain entry terms, date introduced, previous indexing, automatic explosionInclude the objectives here