• Article by Gerald J. Cox, Charles F. Baily, and Robert S. Casey in Chemical and Engineering News, "Punched Cards for a Chemical Bibliography," is first to bring punched cards to attention of chemists.

1946

• ACS Board establishes a Board Committee on Punched Cards, with James W. Perry as chairman. The Committee's activities are financially supported by the ACS with additional funds solicited from industry. Massachusetts Institute of Technology's Center for Scientific Aids to Learning continues this work with a grant from the Carnegie Corporation.
• Chemical Biological Coordination Center (CBCC) is established in the U.S. National Academy of Sciences/National Research Council. Begins punched card system to organize complex information files.
• G. Malcolm Dyson presents a paper before London's Royal Institute of Chemistry on his notation system, which seeks to represent chemical structures uniquely and unambiguously in a linear sequence of letters and numbers. IUPAC provisionally recommends the Dyson system.

1947

• William E. Batten, Imperial Chemical Industries in Great Britain, reports on the use of optical coincidence cards for information retrieval.

1948

• Calvin Mooers develops concept of Zatocoding, using "descriptors" and random coding on mechanically sorted edge-notched cards.
• James W. Perry and G. Malcolm Dyson discuss with Thomas J. Watson, IBM president, the need to develop a machine to handle large volumes of scientific information, particularly chemical information. Watson agrees to work on the problem and assigns Hans Peter Luhn to the project.
• Welch Medical Library Indexing Project at Johns Hopkins University begins. Sponsored by the Army Medical Library (now the National Library of Medicine), it was one of the first efforts to study medical and chemical nomenclature and indexing and to apply machine technologies to this information.

1949

• George Willard Wheland, professor at the University of Chicago, develops basic concept of the connection table to represent chemical structures.
• William J. Wiswesser introduces Wiswesser Line Notation.

1950

• Hans Peter Luhn develops prototype of the Luhn Scanner for IBM. Its technology is based on IBM punched cards, run vertically through a specially adapted scanner, using photo-electric cells. It does not require fixed-field searching. It is first demonstrated at the World Chemical Conclave in New York City, September 1951.
• The Information for Industry Index to U.S. Patents (IFI/Plenum) begins publication using Mortimer Taube's Uniterm system for index terms.

1951

• Mortimer Taube and Alberto F. Thompson of the AEC Technical Information Service present "The Coordinate Indexing of Scientific Fields" before the Symposium on Mechanical Aids to Chemical Documentation sponsored by the ACS's Division of Chemical Literature. This paper contains the first use of the term coordinate indexing.
• James W. Perry and Robert S. Casey publish Punched Cards: Their Application to Science and Industry. A second edition appeared in 1958 with Madeline Berry and Allen Kent as co-authors.
• At Johns Hopkins University's Welch Medical Library, Eugene Garfield develops machine methods for compiling Current List of Medical Literature (later merged with Index Medicus) and applies the IBM 101 punched-card sorter to search this database.
• At Sharp and Dohme, Claire Schultz employs Calvin Mooers's superimposed coding and the Remington Rand punched-card sorter to perform chemistry searches.
• In Great Britain, Derwent Publications, Ltd., begins patent abstracting services with Central Patents Index. Punched cards are used to construct the indexes.

1952

• Karl Heumann and Raimon Beard report on the U.S. National Research Council's Chemical-Biological Coordination Center survey of the use of punched cards, classification systems, etc. in documenting work in the chemistry and biology fields.

1954

• In France, Jacques-Emile Dubois does initial work on the DARC (Description, Acquisition, Retrieval, and Correlation) system.

1955

• Chemical Abstract Services (CAS) establishes research and development unit.

1957

• Eugene Garfield Associates, Inc., begins project with Pharmaceutical Manufacturers Association to scan and index the current literature on steroid compounds. The coding sheets produced are then used by the U.S. Patent Office to make punched cards for searching by patent examiners to find current literature. This project leads indirectly to Index Chemicus.

1958

• Hans Peter Luhn (IBM) and Herbert Ohlman (System Development Corporation) display first key word in context (KWIC) indexes at ICSI.
• Eugene Garfield Associates publishes first issues of Current Contents/Life Sciences, covering life sciences, pharmacy, and chemistry in a format that was prototyped in 1952. Garfield also begins work on his algorithm for converting chemical names into molecular formulas.

1965

• CAS markets microfilms of all abstracts published since 1907.