Artificial intelligence is the broad field of building computer systems that simulate human-like intelligence, such as learning, inference, and reasoning. Historically, early AI included rule-based approaches and expert systems. Machine learning later became a major shift because instead of hand-coding every rule, the system learns patterns from data and uses them for prediction or anomaly detection. Deep learning is a subset of machine learning that uses multi-layer neural networks. These networks are inspired by the brain, though only loosely and imperfectly. Deep learning improved the performance of many AI systems, but it can also make decisions that are harder to interpret because the internal reasoning is distributed across many layers. Generative AI is the newest major wave and is built on foundation models, especially large language models. These models do not just classify or predict; they generate new content such as text, summaries, audio, video, and synthetic voices. Chatbots and deepfakes are examples of this category. The video emphasizes that these technologies are related hierarchically, and that generative AI has driven the recent explosion in public adoption.