Marine bearings are critical components in ship propulsion and mechanical systems, designed to withstand harsh ocean environments, including saltwater corrosion, heavy loads, and continuous operation. Common types include stern tube bearings (oil/water-lubricated), thrust bearings (handling propeller forces), and roller bearings (for auxiliary machinery). They are typically made from wear-resistant materials like bronze, white metal, or composites with advanced coatings. Key features include high load capacity, low friction, and compliance with classification society standards (e.g., ABS, DNV). Proper lubrication (oil, grease, or water) ensures longevity and reliability, making marine bearings vital for safe and efficient vessel operation.