Explores the general importance of the concepts of type and quality of knowledge for theory, research and practice in the field of learning and instruction. Declarative and procedural knowledge as popular examples; Characteristics; Levels.

Research in learning and instruction claims a central role for the concept of knowledge. The knowledge base of a person, it is now generally assumed, is made up of different types of knowledge. The most well-known examples are declarative and procedural knowledge, but more elaborate distinctions exist. Futthermore, the knowledge base is characterized by different qualities, such as level (deep or surface) of knowledge, generality of knowledge, level of autornization of knowledge, modality of knowledge, and structure of knowledge. The present article examines the concept ofknowledge by presenting a matrix that takes types and qualities of knowledge as its dimensions. This matrix can be used to classify research on knowledge by linking aspects such as knowledge assessment techniques, expert-beginner differences, instructional measures, and learning goals to the cells of the matrix.