Recommender systems are a specialized class of machine learning algorithms designed to predict a user's preferences and suggest relevant items, such as products, movies, or articles. By analyzing vast datasets of user behavior (like past ratings, purchases, or clicks) and item attributes, these systems identify patterns to make personalized suggestions. The two primary approaches are collaborative filtering, which leverages the preferences of similar users, and content-based filtering, which recommends items similar to those a user has previously liked. As a practical application of AI, recommender systems are crucial for navigating information overload and are fundamental to the user experience on platforms like Netflix, Amazon, and Spotify.