Heart disease refers to a range of conditions affecting the heart's structure and function, including coronary artery disease, arrhythmias, and heart valve issues. It's often linked to plaque buildup in the arteries, restricting blood flow to the heart, leading to chest pain (angina) or a heart attack. Risk factors like high cholesterol, high blood pressure, smoking, and diabetes contribute to its development. Symptoms vary but commonly include chest discomfort, shortness of breath, and fatigue. Treatment involves lifestyle changes, medication, and, in severe cases, procedures like angioplasty, emphasizing prevention and management for better heart health.