CBT and RET are both terms related to psychotherapy. CBT stands for Cognitive-Behavioral Therapy while RET stands for Rational Emotive Therapy. CBT is actually the catch-all term for a group of therapeutic approaches. RET is one of the several approaches included under the CBT umbrella.
Cognitive-Behavioral Therapy is a category of therapeutic techniques. Among the CBT approaches are: Rational Emotive Therapy, Rational Behavior Therapy, Rational Living Therapy, Cognitive Therapy, Dialectical Behavior Therapy and Schema Focused Therapy. Therapists began embracing CBT during the 1950s, though its philosophical origins are found in ancient Greece. Through CBT, therapists endeavour to help clients understand and modify their own behaviour and thinking.
The first CBT approach to gain popularity with therapists was RET, or Rational Emotive Therapy. Albert Ellis developed RET in 1955. Ellis based his approach on the philosophy of ancient Stoicism. Ellis believed that individuals are more affected by their perceptions of events than by the events themselves. Ellis created a systematic technique for clients known as the "ABC Model of Emotions," later renamed by Ellis as "ABCDE Model." With this model, Ellis endeavoured to encourage individuals to take responsibility for their own negative thinking and work toward more positive perceptions. In the 1990s, Albert Ellis renamed his technique "Rational Emotive Behavior Therapy" or REBT.
The basis of RET is the ABCDE Model of Emotions. The ABCDE Model is a technique individuals can use to deal with negative emotions and beliefs. The "A" refers to the "Activating event." These are times that life is not going well for the individual. The "B" stands for "Beliefs." This refers to how the individual perceives the activating event. For example, if her car runs out of gas, does the individual believe she was at fault for not filling the tank or does she believe that it is part of a plot against her. The "C" refers to "Consequences," or how the individual reacts or feels about the event. The individual must analyse whether her reaction was positive or negative. "D" stands for "Disputing." At this point, the individual must determine whether her beliefs are rational or irrational. If she finds that her beliefs are irrational, she must dispute them based upon empirical evidence or her own logic. The "E" refers to "Effect." At this stage, the individual creates more rational beliefs based upon logic or evidence related to the situation.
The difference between the two terms CBT and RET are further complicated by their being used interchangeably by therapists and in psychotherapy publications. CBT is the name for the overall category of approaches, while RET is the name for a specific approach. Therefore, RET is a type of CBT.