The National Library of Medicine (NLM) is the world's largest medical library and is a part of the National Institutes of Health (NIH) in the United States. The NLM is located in Bethesda, Maryland, and is responsible for acquiring, preserving, and disseminating biomedical literature and information to advance research and improve public health. The NLM maintains a number of resources and databases, including PubMed, a database of biomedical literature, and the MEDLINE database, which contains abstracts and citations for medical journal articles. The NLM also operates the National Center for Biotechnology Information (NCBI), which provides access to genomic and other biomedical data, and the National Institutes of Health's Clinical Center, which conducts clinical research studies. The NLM is a valuable resource for researchers, healthcare professionals, and the general public.