The Evolution of Bloom's Taxonomy

The Evolution of Bloom's Taxonomy


For over 60 years, Bloom's taxonomy has been used as an instructional design tool to create curriculum, activities, and assessments, with the goal to ensure that all orders of thinking are exercised in students' learning process, including their ability to search for information. 

The original taxonomy was a set of three hierarchical models that classified learning objectives into levels of complexity. It was created in 1956 by Benjamin Bloom with collaborators Max Englehart, Edward Furst, Walter Hill, and David Krathwohl and published in Taxonomy of Educational Objectives: The Classification of Educational Goals.

In 2001, a group of cognitive psychologists, curriculum theorists, instructional researchers, and testing and assessment specialists published a revision of Bloom’s Taxonomy with the title A Taxonomy for Teaching, Learning, and Assessment. This title draws attention away from the static notion of “educational objectives” (in Bloom’s original title) and points to a more dynamic concept of classification.

In this module, we will look at the evolution of Bloom's taxonomy and the contributions by other researchers and educators to make it relevant to changing education scenarios. 

Original Taxonomy (1956)

The original taxonomy was published in 1956 in Taxonomy of Educational Objectives. It focused on three domains: Cognitive (knowledge-based), Affective (emotion-based), and Psychomotor (action-based).


This list has been the primary focus of most traditional education and is frequently used to structure curriculum learning objectives, assessments and activities. In the original (1956) version, the cognitive domain was broken into six levels: Knowledge, Comprehension, Application, Analysis, Synthesis and Evaluation.  The categories after Knowledge were presented as “skills and abilities,” with the understanding that knowledge was the necessary precondition for putting these skills and abilities into practice. (In 2001, a revised edition of the Taxonomy was created where the levels were revised as: Remember, Understand, Apply, Analyze, Evaluate, and Create. This is covered later in this module.)

cognitive domain

The 6 cognitive levels as outlined in the original taxonomy are:

  1. Knowledge: Knowledge involves recognizing or remembering facts, terms, basic concepts, or answers without necessarily understanding what they mean. Its characteristics may include Knowledge of specifics—terminology, specific facts, Knowledge of ways and means of dealing with specifics—conventions, trends and sequences, classifications and categories, Knowledge of the universals and abstractions in a field—principles and generalizations, theories and structures. Example: Name three varieties of apples.
  2. Comprehension: Comprehension involves demonstrating an understanding of facts and ideas by organizing, summarizing, translating, generalizing, giving descriptions, and stating the main ideas. Example: Summarize the identifying characteristics of a Golden Delicious apple and a Granny Smith apple.
  3. Application: Application involves using acquired knowledge—solving problems in new situations by applying acquired knowledge, facts, techniques and rules. Learners should be able to use prior knowledge to solve problems, identify connections and relationships and how they apply in new situations. Example: Would apples prevent scurvy, a disease caused by a deficiency in vitamin C?
  4. Analysis: Analysis involves examining and breaking information into component parts, determining how the parts relate to one another, identifying motives or causes, making inferences, and finding evidence to support generalizations. Its characteristics include: Analysis of elements, Analysis of relationships and Analysis of organization. Example: Compare and contrast four ways of serving foods made with apples and examine which ones have the highest health benefits
  5. Synthesis: Synthesis involves building a structure or pattern from diverse elements; it also refers to the act of putting parts together to form a whole. Its characteristics include: Production of a unique communication, Production of a plan, or proposed set of operations, and Derivation of a set of abstract relations. Example: Convert an "unhealthy" recipe for apple pie to a "healthy" recipe by replacing your choice of ingredients. Argue for the health benefits of using the ingredients you chose versus the original ones.
  6. Evaluation: Evaluation involves presenting and defending opinions by making judgments about information, the validity of ideas, or quality of work based on a set of criteria. Its characteristics include: Judgments in terms of internal evidence, and Judgments in terms of external criteria. Example: Which kinds of apples are best for baking a pie, and why?


Skills in the affective domain describe the way people react emotionally and their ability to feel other living things' pain or joy. Affective objectives typically target the awareness and growth in attitudes, emotions, and feelings.

affective domain

There are five levels in the affective domain moving through the lowest-order processes to the highest.

  1. Receiving: The lowest level; the student passively pays attention. Without this level, no learning can occur. Receiving is about the student's memory and recognition as well.
  2. Responding: The student actively participates in the learning process, not only attends to a stimulus; the student also reacts in some way.
  3. Valuing: The student attaches a value to an object, phenomenon, or piece of information. The student associates a value or some values to the knowledge they acquired.
  4. Organizing: The student can put together different values, information, and ideas, and can accommodate them within his/her own schema; the student is comparing, relating, and elaborating on what has been learned.
  5. Characterizing: The student at this level tries to build abstract knowledge.


The psychomotor domain describes the ability to physically manipulate a tool or instrument like a hand or a hammer. Psychomotor objectives usually focus on change and/or development in behavior and/or skills. This domain was not broken down into subcategories for skills in the original taxonomy.

Image credits: By Corydave - Own work, CC0

Psychomotor Skill Hierarchy (1972)

In 1972, Elizabeth Simpson, an educator at the University of Illinois proposed a hierarchy for Bloom’s aforementioned psychomotor domain, with the following seven levels:

psychomotor domain

  1. Perception - The ability to use sensory cues to guide motor activity: This ranges from sensory stimulation, through cue selection, to translation. Examples: Detects non-verbal communication cues. Estimate where a ball will land after it is thrown and then moving to the correct location to catch the ball. Adjusts heat of the stove to correct temperature by smell and taste of food. Adjusts the height of the forks on a forklift by comparing where the forks are in relation to the pallet. Key words: chooses, describes, detects, differentiates, distinguishes, identifies, isolates, relates, selects.
  2. Set - Readiness to act: It includes mental, physical, and emotional sets. These three sets are dispositions that predetermine a person's response to different situations (sometimes called mindsets). This subdivision of psychomotor is closely related with the "responding to phenomena" subdivision of the affective domain. Examples: Knows and acts upon a sequence of steps in a manufacturing process. Recognizes his or her abilities and limitations. Shows desire to learn a new process (motivation). Keywords: begins, displays, explains, moves, proceeds, reacts, shows, states, volunteers.
  3. Guided response - The early stages of learning a complex skill that includes imitation and trial and error: Adequacy of performance is achieved by practicing. Examples: Performs a mathematical equation as demonstrated. Follows instructions to build a model. Responds to hand-signals of the instructor while learning to operate a forklift. Keywords: copies, traces, follows, reacts, reproduces, responds.
  4. Mechanism- The intermediate stage in learning a complex skill: Learned responses have become habitual and the movements can be performed with some confidence and proficiency. Examples: Use a personal computer. Repair a leaking tap. Drive a car. Key words: assembles, calibrates, constructs, dismantles, displays, fastens, fixes, grinds, heats, manipulates, measures, mends, mixes, organizes, sketches.
  5. Guided (complex overt) response -The skillful performance of motor acts that involve complex movement patterns: Proficiency is indicated by a quick, accurate, and highly coordinated performance, requiring a minimum of energy. This category includes performing without hesitation and automatic performance. For example, players will often utter sounds of satisfaction or expletives as soon as they hit a tennis ball or throw a football because they can tell by the feel of the act what the result will produce. Examples: Maneuvers a car into a tight parallel parking spot. Operates a computer quickly and accurately. Displays competence while playing the piano. Key words: assembles, builds, calibrates, constructs, dismantles, displays, fastens, fixes, grinds, heats, manipulates, measures, mends, mixes, organizes, sketches. (Note: The key words are the same as in mechanism, but will have adverbs or adjectives that indicate that the performance is quicker, better, more accurate, etc.)
  6. Adaptation - Skills are well developed and the individual can modify movement patterns to fit special requirements. Examples: Responds effectively to unexpected experiences. Modifies instruction to meet the needs of the learners. Performs a task with a machine that was not originally intended for that purpose (the machine is not damaged and there is no danger in performing the new task). Key words: adapts, alters, changes, rearranges, reorganizes, revises, varies.
  7. Origination - Creating new movement patterns to fit a particular situation or specific problem: Learning outcomes emphasize creativity based upon highly developed skills. Examples: Constructs a new set or pattern of movements organized around a novel concept or theory. Develops a new and comprehensive training program. Creates a new gymnastic routine. Key words: arranges, builds, combines, composes, constructs, creates, designs, initiates, makes, originates.

Revised Taxonomy (2001)

In 2001, a group comprising cognitive psychologists, curriculum theorists, instructional researchers, and testing and assessment specialists published a revision of Bloom’s Taxonomy. The new title was called e A Taxonomy for Teaching, Learning, and Assessment. It notably drew attention away from the somewhat static notion of “educational objectives” in Bloom’s original title and pointed to a more dynamic conception of classification.

Revised Taxonomy

The authors of the revised taxonomy underscored this dynamism, using verbs to label their categories and subcategories (rather than the nouns as found in the original taxonomy). These “action words” describe the cognitive processes by which thinkers encounter and work with knowledge:

  • Remember
    • Recognizing
    • Recalling
  • Understand
    • Interpreting
    • Exemplifying
    • Classifying
    • Summarizing
    • Inferring
    • Comparing
    • Explaining
  • Apply
    • Executing
    • Implementing
  • Analyze
    • Differentiating
    • Organizing
    • Attributing
  • Evaluate
    • Checking
    • Critiquing
  • Create
    • Generating
    • Planning
    • Producing

In the revised taxonomy, knowledge is at the basis of these six cognitive processes, but its authors created a separate taxonomy of the types of knowledge used in cognition:

  • Factual Knowledge
    • Knowledge of terminology
    • Knowledge of specific details and elements
  • Conceptual Knowledge
    • Knowledge of classifications and categories
    • Knowledge of principles and generalizations
    • Knowledge of theories, models, and structures
  • Procedural Knowledge
    • Knowledge of subject-specific skills and algorithms
    • Knowledge of subject-specific techniques and methods
    • Knowledge of criteria for determining when to use appropriate procedures
  • Metacognitive Knowledge
    • Strategic Knowledge
    • Knowledge about cognitive tasks, including appropriate contextual and conditional knowledge
    • Self-knowledge

Mary Forehand from the University of Georgia provides a guide to the revised version giving a brief summary of the revised taxonomy and a helpful table of the six cognitive processes and four types of knowledge.


Bloom's taxonomy serves as the backbone of many teaching philosophies, in particular, those that lean towards skills rather than content. These educators view content as a vessel for teaching skills. The taxonomy is widely implemented as a hierarchy of verbs, designed to be used when writing learning outcomes. A 2020 analysis showed that these verb lists were not consistent across educational institutions, and learning outcomes that were mapped to one level of the hierarchy at one educational institution could be mapped to different levels at another institution

The skill development that takes place at higher orders of thinking interacts well with a developing global focus on multiple literacies and modalities in learning and the emerging field of integrated disciplines. The ability to interface with and create media would draw upon skills from both higher-order thinking skills (analysis, creation, and evaluation) and lower-order thinking skills (knowledge, comprehension, and application). The authors of the revised taxonomy suggested a multi-layered answer to this question. Below are their thoughts, along with some clarifications by Patricia Armstrong, Vanderbilt University:

  1. Objectives (learning goals) are important to establish in a pedagogical interchange so that teachers and students alike understand the purpose of that interchange.
  2. Teachers can benefit from using frameworks to organize objectives because
  3. Organizing objectives helps to clarify objectives for themselves and for students.
  4. Having an organized set of objectives helps teachers to:
    • “plan and deliver appropriate instruction”;
    • “design valid assessment tasks and strategies”;and
    • “ensure that instruction and assessment are aligned with the objectives.”

Both the original and revised taxonomies continue to be a source of inspiration for educational philosophy and for developing new teaching strategies.


  1. Bloom, B. S.; Engelhart, M. D.; Furst, E. J.; Hill, W. H.; Krathwohl, D. R. (1956). Taxonomy of educational objectives: The classification of educational goals. Handbook I: Cognitive domain. New York: David McKay Company.
  2. Simpson, Elizabeth J. (1966). The classification of educational objectives: Psychomotor domain. Illinois Journal of Home Economics. 10 (4): 110–144.
  3. Dave, R. H. (1975). Armstrong, R. J. (ed.). Developing and writing behavioral objectives. Tucson: Educational Innovators Press.
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  5. Armstrong, Patricia. (2010). Bloom’s Taxonomy. Vanderbilt University Center for Teaching. Retrieved 7/30/2021 from .
  6. Simpson, Elizabeth (1972). Educational objectives in the psychomotor domain. 3. Washington, D.C.: Gryphon House: 25–30.
  7. Paul, R. (1993). Critical thinking: what every person needs to survive in a rapidly changing world (3rd ed.). Rohnert Park, California: Sonoma State University Press.
  8. Vygotsky, L. S. (1978). “Chapter 6: Interaction between learning and development.” Mind in society: the development of higher psychological processes. Cambridge, Massachusetts: Harvard University Press. pp. 79–91.
  9. Keene, Judith; Colvin, John; Sissons, Justine (June 2010) [2010]. Mapping student information literacy activity against Bloom's taxonomy of cognitive skills". Journal of Information Literacy. 4 (1): 6–21. doi:10.11645/4.1.189
  10. Newton, Philip M.; Da Silva, Ana; Peters, Lee George (10 July 2020). "A pragmatic master list of action verbs for Bloom's taxonomy". Frontiers in Education. 5. doi:10.3389/feduc.2020.00107.
  11. BJ Jansen, D Booth, B Smith (2009) Using the taxonomy of cognitive learning to model online searching, Information Processing & Management 45 (6), 643-663
  12. Anderson, Lorin W., David R. Krathwohl, and Benjamin S. Bloom. A Taxonomy for Learning, Teaching, and Assessing: a Revision of Bloom’s Taxonomy of Educational Objectives / Editors, Lorin W. Anderson, David Krathwohl; Contributors, Peter W. Airasian ... [et Al.]. Complete ed. New York: Longman, 2001.