IBM Rational Team Concert was created in 2008-06.
IBM Rational Application Developer was created on 2005-01-07.
IBM Rational Software Modeler was created on 2004-10-13.
IBM Rational solution for Collaborative Lifecycle Management was created in 2011-06.
IBM Rational is a service provided by IBM. IBM Rational helps with software and systems development. It is supposed to help software be more profitable and and improve productivity.
Req Pro was a part of the original Rational suite (Rational Rose, Rational Clear Case). DOORS Was a major competitor to Req Pro, later IBM bought it and renamed it to Rational DOORS. So now you have two requirement tools under IBM. DOORS is generally used by Systems Engineering companies and ReqPro by IT companies. Presently IBM is developing another product based on their open source intiative - jazz.net; which is called Rational Requirements Composer. RRC can be considered next generation version of ReqPro
Rational Unified Process
IBM BASIC was created in 1981.
IBM CPC was created in 1949.
IBM AIX was created in 1986.
IBM RPG was created in 1959.
IBM Award was created in 1984.
IBM JX was created in 1984.