In 1956, Benjamin Bloom, with collaborators, published a framework for categorizing educational goals, which comprises three learning domains—cognitive, affective, and psychomotor—and assigned to each of these domains a hierarchy that corresponds to different levels of learning.

Cognitive Domain	Psychomotor Domain	Affective Domain
Knowledge ↓ Comprehension ↓ Application ↓ Analysis ↓ Synthesis ↓ Evaluation	Imitation ↓ Manipulation ↓ Precision ↓ Articulation ↓ Naturalization .	Receiving ↓ Responding ↓ Valuing ↓ Organization ↓ Characterization .

Bloom’s Taxonomy Revised

In 2001, one of Bloom’s original collaborators and co-editors published a revision to the 1956 hierarchy. This new revised version introduced a key change to the cognitive domain of Bloom’s Taxonomy.

Cognitive Domain

Remember ↓ Understand ↓ Apply ↓ Analyze ↓ Evaluate ↓ Create