Classical Conditioning is a learning process where a neutral stimulus becomes associated with a meaningful stimulus, leading to a learned response. This concept was first studied by Ivan Pavlov, a Russian physiologist, who discovered it while observing dogs. He noticed that dogs would salivate not only when food was presented but also when they heard the sound of a bell that had been paired with food. In this process, the neutral stimulus (like the bell) is repeatedly paired with an unconditioned stimulus (like food) that naturally triggers a response (salivation). After several pairings, the neutral stimulus alone can evoke the same response, now called a conditioned response.