Unsupervised machine learning is a type of artificial intelligence where algorithms analyze unlabeled data to identify hidden patterns, structures, and relationships without predefined answers. Unlike supervised learning, which uses labeled datasets with known outputs, unsupervised learning works independently to explore and organize data. Common techniques include clustering, where similar data points are grouped together, and dimensionality reduction, which simplifies complex datasets while preserving important information. These methods are widely used in customer segmentation, anomaly detection, recommendation systems, and data visualization. Although unsupervised learning is powerful for discovering insights, interpreting the results can sometimes be difficult because there are no labeled references for accuracy comparison.