Medline is Operational at the U.S. National Library of Medicine

In October 1971 Medline (Medical Literature Analysis and Retrieval System Online), a literature database of life sciences and biomedical information, was operational at the National Library of Medicine. It was initially a database version of the printed Index Medicus.

By 2019 Medline  ontained "more than 25 million" records from approximately 5,000 selected publications covering biomedicine and health from 1950 to the present.