Calcium is the mineral essential for maintaining strong bones. It plays a critical role in bone structure, strength, and density. Adequate calcium intake is vital throughout a person's life, particularly during adolescence and in older age when bone density tends to decline. Calcium also aids in various bodily functions, including muscle contraction, blood clotting, and nerve transmission. Foods rich in calcium include dairy products, leafy greens, and fortified foods. Additionally, vitamin D is important for calcium absorption in the body. A balanced diet that includes these nutrients can help prevent osteoporosis and other bone-related disorders.