Machine learning is a branch of artificial intelligence that uses computing systems to analyze data, recognize patterns and make decisions with minimal human involvement. There are two main types of machine learning: supervised learning, where the model learns from labeled examples with known outcomes, and unsupervised learning, where the model finds hidden patterns in unlabeled data. The machine learning process involves defining objectives, preparing data through techniques like normalization and feature engineering, building models, evaluating models on test data, and deploying selected models.