"One of the distinct features of XP is the lack of any documentation whatsoever, except for the code itself. This is a contraposition to the modeling techniques like the Unified Modeling Language , which strongly focus on documentation. XP takes an extreme position there, not even documenting the architecture of the system. Often, it is very difficult to extract the overall structure, behavior or interactions with the environment from the code. The code is a rather detailed and fragile representation of the system’s tasks. Even though the code contains all necessary information about the system, this information is often burdened with details and it is tedious to extract the aspects one is interested in. Therefore, it would be useful to have a more compact system representation. The UML does provide a number of notations that are suited for this purpose. However, the tools so far are not capable of supporting UML in such a manner that it can be well-integrated with the approach of Extreme Programming."

“Advances in hardware and network technologies have paved the way for the development of increasingly pervasive software-based that collaborate to provide essential services to society. Software in these systems is often required to operate in distributed and embedded computing environments consisting of diverse devices , communicate using a variety of interaction paradigms , dynamically adapt to changes in operating environments, and behave in a dependable manner. Despite significant advances in programming languages and supporting integrated development environments , developing these complex software systems using current code-centric technologies requires herculean effort.”

“In all engineering disciplines nowadays, software engineering excluded, there exists an established engineering process to develop a system, which is accompanied by a number of suited modeling description techniques. Software engineering, being a rather new field, has not as yet established any clear methodical guidance or a fully standardized modeling notation.”

“The term is typically used to describe software development approaches in which abstract models of software systems are created and systematically transformed to concrete implementations.... Full realizations of the MDE vision may not be possible in the near to medium-term primarily because of the wicked problems involved. On the other hand, attempting to realize the vision will provide insights that can be used to significantly reduce the gap between evolving software complexity and the technologies used to manage complexity.”

“The growing complexity of software is the motivation behind work on industrializing software development. In particular, current research in the area of is primarily concerned with reducing the gap between problem and software implementation domains through the use of technologies that support systematic transformation of problem-level abstractions to software implementations. The complexity of bridging the gap is tackled through the use of models that describe complex systems at multiple levels of abstraction and from a variety of perspectives, and through automated support for transforming and analyzing models. In the MDE vision of software development, models are the primary artifacts of development and developers rely on computer-based technologies to transform models to running systems.”

“Today some evidence arises that UML will more and more be used not as a but as a high level programming language. This has some advantages, as if the concepts of UML are executable, they can immediately be animated and tested, or the generated code even be used as implementation. Thus UML probably will have an implementation-oriented semantics describing this animation.”

“Originally UML was intended to serve as a. But a specification is primarily intended to describe properties of systems that the system developers want to be valid, but to leave open other properties that are not clear already. Today this is partly achieved by having a semantics that is rather vague . However, this is not an advantage, as the developer cannot fix this kind of impreciseness within UML, but can adapt the individual interpretation only. Furthermore, to get complete UML descriptions, often certain details have to be specified, which the developer does not yet know or wants to leave open to a later phase of development or even implementation. It is an intrinsic problem of executable languages that this kind of over-specification frequently occurs. Instead it would be of some help to have flexible concepts of under-specification to postpone detail decisions to situations, where the decisions can and must be made.”