There are many definitions and forms of knowledge. It can be described as the body of concepts and factual information (data), including their interrelated structures and patterns, concerning the natural and social environment as well as our understanding of the world, people and society, gained through learning and/or experience. Declarative knowledge points to ‘knowing what’ (e.g. factual knowledge), while procedural knowledge to ‘knowing how’, e.g. knowledge of specific functions and procedures to perform a complex process, task or activity. Other forms of knowledge often considered are tacit and explicit knowledge (see, for example, CEDEFOP 2011). The former is knowledge learners possess which influences cognitive processing; however, they may not necessarily express it or be aware of it. The latter is knowledge a learner is conscious of, including tacit knowledge that converts into an explicit form by becoming an ‘object of thought’.
