MARK IV is a Fourth-generation programming language that was created by Informatics, Inc. (later, Sterling Software) in the 1960s. Informatics, Inc. took advantage of IBM's decision to unbundle their software; MARK IV was the first "software product to have cumulative sales of $10 million".
MARK IV was developed for IBM Systems (360 and 370) and for the RCA Spectra 70. Its main benefit was allowing faster application development on the order of 6 to 10 times faster than doing a system using a 3GL, such as COBOL. MARK IV, being an early 4GL, allowed user development of systems related to business. In an 1971 ad by Informatics, there are several quotes from customers, such as:
MARK IV (as VISION:BUILDER) is now part of the product suite from Computer Associates.