Supervised Learning
Supervised learning is the most intuitive way machines learn: you show the system lots of examples with the correct answers attached, and it figures out the pattern. Show it a thousand emails labelled "spam" or "not spam" and it learns to sort your inbox. Show it medical scans labelled with diagnoses and it learns to flag potential problems. The word "supervised" comes from the fact that a human has provided the right answers - the labels - that the model learns from. It is the most widely used approach in commercial AI because it's reliable and well-understood. When you have a clearly defined task and enough good examples of correct answers, supervised learning often works well. The main limitation is that it requires large quantities of labelled data, which can be expensive and time-consuming to produce. The quality of those labels matters enormously: if the examples are wrong, inconsistent, or biased, the model learns those mistakes just as faithfully as it learns the correct patterns.