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With the Rational June 2006 Product Release, IBM withdrew the “XDE” family of products and introduced the Rational Rose family of products as replacements.
The Rational Rose family of products is a set of UML modeling tools for software design. The Unified Modeling Language (UML) is the industry-standard language for specifying, visualizing, constructing, and documenting the artifacts of software systems. It simplifies the complex process of software design, creating a "blueprint" for construction of software systems.
The Rational Rose family is for customers wishing to integrate with legacy integrated development environments or languages. For more modern architectures Rational Software Architect and Rational Software Modeler were developed. These products were created matching and surpassing Rose XDE capabilities to include support for UML 2.x, pattern customization support, the latest programming languages and approaches to software development such as SOA and more powerful data modeling that supports Entity-Relationship modeling.