Articular cartilage is a specialized connective tissue found in diarthrodial joints, primarily serving to provide a smooth, lubricated surface for articulation and to transmit loads with low friction. It lacks blood vessels, lymphatics, and nerves, and has limited intrinsic healing capacity. The tissue is composed of a dense extracellular matrix (ECM) with sparse chondrocytes, primarily type II collagen and proteoglycans. The ECM retains water, which is crucial for maintaining its mechanical properties. Articular cartilage is divided into zones (superficial, middle, deep, and calcified) and regions (pericellular, territorial, and interterritorial) based on structure and composition. Chondrocytes are responsible for matrix synthesis and maintenance, and their metabolic activity is influenced by various factors, including cytokines and growth factors. The biomechanical behavior of articular cartilage is characterized by its viscoelastic properties, which depend on the interaction between the ECM and interstitial fluid. Age-related changes in the ECM and chondrocyte function affect the tissue's structural integrity and function. Noninvasive imaging techniques, such as MRI, are valuable tools for evaluating and monitoring articular cartilage health.Articular cartilage is a specialized connective tissue found in diarthrodial joints, primarily serving to provide a smooth, lubricated surface for articulation and to transmit loads with low friction. It lacks blood vessels, lymphatics, and nerves, and has limited intrinsic healing capacity. The tissue is composed of a dense extracellular matrix (ECM) with sparse chondrocytes, primarily type II collagen and proteoglycans. The ECM retains water, which is crucial for maintaining its mechanical properties. Articular cartilage is divided into zones (superficial, middle, deep, and calcified) and regions (pericellular, territorial, and interterritorial) based on structure and composition. Chondrocytes are responsible for matrix synthesis and maintenance, and their metabolic activity is influenced by various factors, including cytokines and growth factors. The biomechanical behavior of articular cartilage is characterized by its viscoelastic properties, which depend on the interaction between the ECM and interstitial fluid. Age-related changes in the ECM and chondrocyte function affect the tissue's structural integrity and function. Noninvasive imaging techniques, such as MRI, are valuable tools for evaluating and monitoring articular cartilage health.