PubChem is an open chemistry database at the National Institutes of Health (NIH). (“Open” means that you can put your scientific data in PubChem and others may use it). PubChem is a key chemical information resource for scientists, students, and the general public. Records are contributed by government agencies, chemical vendors, journal publishers, and more.
The PubMed database contains more than 30 million citations and abstracts of biomedical literature. 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). It facilitates searching across several NLM resources, including MEDLINE, PubMed Central, and Bookshelf. A well-known medical resource, PubMed's resources are extensive, authoritative, and offer complex searching options. Coverage in this database extends from the 1940s to the present day.