A disease is a condition that disrupts the normal functioning of the body or mind, often leading to symptoms that can affect daily life. Diseases can be caused by various factors, including infections, genetics, and environmental influences. Common examples include diabetes, heart disease, and influenza. Understanding diseases is crucial for prevention and treatment. Many diseases can be managed or cured with proper medical care, lifestyle changes, and medication. Public health initiatives aim to educate people about disease prevention, such as vaccinations for measles and COVID-19, which help reduce the spread of infectious diseases.