Consumer behavior is the process of how consumers decide what, when, where, how, and why to buy goods and services. It is influenced by various factors such as motivation, perception, attitude, learning, and personality. Social media and online communities can have a major impact on consumer behavior by providing and facilitating information such as reviews, recommendations, and feedback to help consumers search and evaluate alternatives. These platforms can also generate emotions, desires, needs, and expectations that can influence consumers' preferences, satisfaction, and loyalty. Additionally, they can modify and reinforce norms, values, beliefs, and attitudes that shape opinions, judgments, and decisions. Finally, they can trigger and reward actions that shape purchase, consumption, and post-purchase behavior.