Abridged Index Medicus via the Teletypewriter Exchange Network

Overview
The Abridged Index Medicus via the Teletypewriter Exchange Network (AIM-TWX) was an experimental on-line bibliographic retrieval system used by the National Library of Medicine (NLM) that used an abridged data base consisting of 5 years of citations from the 100 most important English-language journals in clinical medicine. The system became operational in May 1970, and was so successful that by November 1970 over 80 institutions were using it. The NLM merged the old MEDLARS I with the already successful AIM-TWX system and put the MEDLINE (MEDLARS On-line) service in place in October 1971.