The Rational Unified Process (RUP) is an iterative software development process

Software development process

A software development process, also known as a software development life cycle , is a structure imposed on the development of a software product. Similar terms include software life cycle and software process. It is often considered a subset of systems development life cycle...

 framework created by the Rational Software

Rational Software

Rational Machines was founded by Paul Levy and Mike Devlin in 1981 to provide tools to expand the use of modern software engineering practices, particularly explicit modular architecture and iterative development...

 Corporation, a division of IBM

IBM

International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...

 since 2003. RUP is not a single concrete prescriptive process, but rather an adaptable process framework

Software framework

In computer programming, a software framework is an abstraction in which software providing generic functionality can be selectively changed by user code, thus providing application specific software...

, intended to be tailored by the development organizations and software project teams that will select the elements of the process that are appropriate for their needs.