In 1953, Benjamin Bloom and a group of Educational Psychologists, examined the learning process and developed a classification system of thinking patterns.  These blended together elements from the three domains: cognitive, affective, and psychomotor.  

The six cognitive levels that Bloom proposed are (low to high):

1. Knowledge - the ability to recall, repeat, and name.
2. Comprehension - the ability to explain, describe, translate, and review basic knowledge.
3. Application - the ability to apply, demonstrate, and interpret new situations based on comprehension.
4. Analysis - the ability to see patterns, organize, compare and contrast information. 
5. Synthesis - the ability to generalize, summarize, predict, and design.
6. Evaluation - the ability to criticize, reflect, and assess.

This taxonomy remains one of the most cited in the domain of education today despite is age.  

How does Bloom's Taxonomy apply to my classroom?

Bloom's can apply to you and your classroom in a number of ways.  First, in the Learning Outcomes section of your course syllabus, the choice of key words (a suggested list of words for each level follows) may or may not reflect the level that you desire from your students.  For example in an Anatomy & Physiology course, if a learning outcome stated that, "A student shall be able to name all of the major muscles in the body" and the instructor really wants them to not only name but also interpret their function, then the phrase "able to name" is not appropriate.  Rather, a key word associated with Level three should be used.

The second issue deals with the types of quiz and exam questions used in the course.  Once again, does the style of the question reflect the proper level from Bloom's Taxonomy?  When Bloom did his initial work, he found that a large majority of questions asked on exams were Level one - the recall of basic knowledge.  Thus, a connection between what you value as defined in the Learning Outcomes and what you test for should be in agreement based on Bloom's Taxonomy.

Some suggested key words and question cues for each level

Knowledge: what, when, who, define, list, name, recall, state, label, indicate, tabulate, show, describe.

Comprehension: compare, contrast, predict, distinguish, explain, rephrase, illustrate, infer, summarize, interpret, associate, estimate, differentiate, discuss.

Application: apply, develop, test, solve, indicate, demonstrate, calculate, complete, show, examine, modify, relate, change, classify, experiment, discover.

Analysis: analyze, describe, classify, discriminate, distinguish, relate, explain, contrast, assume, separate, order.

Synthesis: create, propose, suggest, make up, formulate, synthesize, derive, combine, integrate, modify, rearrange, design, invent, rewrite.

Evaluation: evaluate, judge, select, defend, determine, assess, rank, grade, test, recommend, convince.

The five affective domains are (low to high):

1. Receiving - a willingness to receive or attend certain stimuli.  This can be further broken into three subcategories - awareness, willingness to receive, and controlled or selected attention.
2. Responding - the active participation by the student.  
3. Valuing - the student sees worth or value in the activity or assignment.
4. Organizing - bringing together a variety of values, possibly conflicting ones, and then resolving them to produce an internal value system.
5. Characterizing - internal values are well established producing a consistent life style.

Each of these also can be associated with some key verbs as well.

Receiving: acknowledge, ask, attend, be aware, choose, describe, follow, give, hold, identify, listen, locate, name, receive, reply, select, show alertness, tolerate, use, view, watch.

Responding: agree (to), answer, ask, assist, communicate, comply, consent, conform, contribute, cooperate, discuss, follow-up, greet, help, indicate, inquire, label, obey, participate, pursue, question, react, read, reply, report, request, respond, seek, select, visit, volunteer, write.

Valuing: accept, adopt, approve, complete, choose, commit, describe, desire, differentiate, display, endorse, exhibit, explain, express, form, initiate, invite, join, justify, prefer, propose, read, report, sanction, select, share, study, work.

Organizing: adapt, adhere, alter, arrange, categorize, classify, combine, compare, complete, defend, explain, establish, formulate, generalize, group, identify, integrate, modify, order, organize, prepare, rank, rate, relate, synthesize, systemize.

Characterizing: act, advocate, behave, characterize, conform, continue, defend, devote, disclose, discriminate, display, encourage, endure, exemplify, function, incorporate, influence, justify, listen, maintain, modify, pattern, practice, preserve, perform, question, revise, retain, support, uphold, use.

Finally, the five Psychomotor domains are:

1. Imitation - the ability to repeat an act or skill.
2. Manipulation - a student continues to practice a skill until it becomes habitual.  Student still may not be totally confident in ability.
3. Precision - skills attained provide for a smooth and accurate performance.  A student is sure and confident in their abilities.
4. Articulation - A student can modify or adapt a performance when necessary.  
5. Naturalization - A student can respond without thought - the response is automatic.