Program understandability: feature analysis of modern approaches

One of main features of modern information technologies is the trend toward the integration and open interchange of information resources (knowledge, ontologies, publications, software development components, standards, and other documents). The usefulness of such exchanges is determined by the ability of the user to understand the implication and destination of such resources. Approaches to specifications of information resources in some most popular projects are analyzed, as well as their common and specific conceptual and design solutions and characteristics used to disclose the implication of specifications.