A classification of educational objectives developed in the 1950s by a group of researchers headed by Benjamin Bloom of the University of Chicago. The taxonomy comprises three learning domains — cognitive, affective and psychomotor. The affective domain relates to emotions, attitudes, appreciations, and values, such as enjoying, conserving, respecting, and supporting. It is divided into five main subcategories, namely: receiving, responding, valuing, organization, and characterization. The psychomotor domain refers to the motor-skills or behavioural skills that constitute the relationship between the cognitive process and physical movement in education. The cognitive domain is described as the recall or recognition of knowledge and the development of intellectual abilities and skills. Each domain is organized as a matrix of increasing levels of difficulty, with examples of activities and keywords for describing mastery of each level. With regard to the cognitive domain, the classification provides a way to organize thinking skills into six levels, from the most basic to the more complex levels of thinking (e.g. knowledge, comprehension, application, analysis, synthesis and evaluation). The taxonomy is probably the original reference of the term higher-order thinking. (Adapted from: ASCD; Seel 2012).
During the 1990s Lorin Anderson, one of his former students, updated the taxonomy changing the Bloom's six major categories from noun to verb forms, as the taxonomy reflects different forms of thinking, and thinking is an active process. In the revised Bloom’s taxonomy the six categories and cognitive processes 10 are: remembering (retrieving, recognizing, and recalling relevant knowledge); understanding (constructing meaning through interpreting, exemplifying, classifying, summarizing, inferring, comparing, and explaining); applying (carrying out or using a procedure through executing, or implementing); analysing (breaking information into parts to explore understanding and relationships through differentiating, organizing, and attributing); evaluating (making judgements based on criteria and standards through checking and critiquing); and creating (putting elements together to form a coherent or functional whole; generating new ideas, products or ways of viewing things). Higher-order thinking refers to the cognitive processes of analysing, evaluating and creating. (Source: Anderson & Krathwohl 2001). There are also other revised versions of the Bloom’s taxonomy.