With the success of numerous applications of the Web 2.0 the interest in a web-based support of scientific communities has also gained significant relevance. The concept of Wikis, one building block of the Web 2.0, has shown to be a reasonable infrastructure for sharing and refining any kind of knowledge. The most prominent example is the encyclopedia Wikipedia,but many smaller wiki applications have proved to be beneficial, e.g., the availability of experience management and documentation projects in opensource communities and large enterprises.
In this paper, we introduce knowledge wikis that extend the features of a regular wiki by the representation and use of explicit problem-solving knowledge. We motivate the general ideas and benefits of knowledge wikis, and we describe a concrete knowledge wiki implementation. The actual use of a knowledge wiki is demonstrated by two case studies: the first case study reports on the share and reuse of ecological domain knowledge in the context of the BIOLOG project; the second case study describes a knowledge formalization pattern repository taken as a demonstrator from the knowledge engineering domain.