Pavlov's classical conditioning is a learning process where a neutral stimulus becomes associated with a meaningful stimulus, leading to a learned response. This concept was developed by Ivan Pavlov, a Russian physiologist, during his experiments with dogs. He discovered that dogs would salivate not only when food was presented but also when they heard a bell that had been paired with the food. In this process, the neutral stimulus (the bell) is repeatedly presented alongside the unconditioned stimulus (the food). Eventually, the neutral stimulus alone can trigger the same response (salivation), now called the conditioned response. This demonstrates how behaviors can be learned through association.