Learning is an action or experience allowing one to acquire knowledge. Every learning process arises from teaching and studying. It aims for a permanent modification of behavior. Learning theories are defined as “attempts to systematize and organize what is known about human learning” (Lefrancois, 2011, p.25). Generally, learning can be classified into three types: classical conditioning, operant conditioning, and cognitive learning (see Figure 1 in Appendix 1). The first type of learning is classical conditioning. This conditioning involves the association of two stimuli, namely the unconditioned stimulus (US) and the conditioned stimulus (CS). This type of conditioning includes three phases throughout the learning process. The first phase is the pre-learning phase, during which the US triggers an unconditioned response (UR), with the response being an unlearned behavior. During this time, the neutral stimulus (NS) does not trigger any reaction. Secondly, the acquisition phase is carried out. US and NS are applied together to stimulate a UR. Finally, the post-learning phase is reached when explicit NS CR, UR is now considered a conditioned stimulus (CR) at this stage. An experiment was carried out by Ivan Pavlov concerning this discovery of classical conditioning. According to research by Pavlov (1927), the clicking of the metronome (NS) did not stimulate the dog's salivation, but the food powder (US) did explain the dog's salivation (UR) (cited in Tarpy, 1997, p.44). However, when the dog was repeatedly presented with both a click and food powder, the dog salivated (UR). At the end, the dog salivated (CR) when only the clicking of the metronome was presented (CS) (Pavlov cited in Tarpy, 1997, p. 44). This experiment showed...... middle of paper ....... (1987). Negative reinforcement in applied behavior analysis: An emerging technology. Journal of Applied Behavior Analysis, 20, 361-378. Lawson, R. & Watson, L. S., Jr. (1963). Positive or negative reinforcement with controlled incentive conditions. The Ohio Journal of Science, 63(2), 87-91. Lefrançois, G. (2011). Theories of human learning: What the teacher said (6th ed.). Belmont: CA. Retrieved from http://books.google.com.my/books?id=SH8DlhiY8QMC Shuell, T. J. (1986). Cognitive conceptions of learning. Review of Educational Research, 56(4),411-436.Tarpy, RM (1997). Contemporary learning theory and research. New York, NY: McGraw-Hill. Wade, C. and Tavris, C. (2005). Invitation to psychology (3rd ed.). Upper Saddle River, NJ: Pearson. Wood, SE, Wood, EG, & Boyd, D. (2006). Mastering the World of Psychology (2nd ed.). Boston, MA: Pearson.