Calvin Northrup Mooers (October 24, 1919 – December 1, 1994), was an American computer scientist known for his work in information retrieval and for the programming language TRAC.

Mooers was a native of Minneapolis, Minnesota, attended the University of Minnesota, and received a bachelor's degree in mathematics in 1941. He worked at the Naval Ordnance Laboratory from 1941 to 1946, and then attended the Massachusetts Institute of Technology, where he earned a master's degree in mathematics and physics. At M.I.T. he developed a mechanical system using superimposed codes of descriptors for information retrieval called Zatocoding. He founded the Zator Company in 1947 to market this idea, and pursued work in information theory, information retrieval, and artificial intelligence.

He coined the term "information retrieval", using it first in a conference paper presented in March 1950. See also a short paper published later that year from Mooers.

He coined "Mooers's law" (not to be confused with Moore's law) and its corollary in 1959:

An information retrieval system will tend not to be used whenever it is more painful and troublesome for a customer to have information than for him not to have it.

Where an information retrieval system tends not to be used, a more capable information retrieval system may tend to be used even less.

He founded the Rockford Research Institute in 1961, where he developed the TRAC programming language, and attempted to control its distribution and development using trademark law and a unique invocation of copyright. (At the time patent law would not allow him to control what he saw as his intellectual property and profit from it.) The trademark strategy was later used by Ada.

Mooers received the American Society for Information Science's Award of Merit in 1978. The citation reads in part: