Calcium compounds are chemical substances that contain the element calcium, which is essential for various biological and industrial processes. Common examples include calcium carbonate, found in rocks and shells, and calcium sulfate, used in plaster and drywall. These compounds play vital roles in construction, agriculture, and food production, providing structural integrity and essential nutrients. In the human body, calcium compounds are crucial for maintaining strong bones and teeth. Calcium phosphate is a key component of bone tissue, while calcium citrate is often used as a dietary supplement. Overall, calcium compounds are important for both health and various applications in everyday life.