A terminal illness is a medical condition that is expected to lead to a person's death within a specific time frame, often within six months to a year. These illnesses are typically progressive and cannot be cured, meaning that treatment focuses on managing symptoms and improving quality of life rather than seeking a cure. Common examples of terminal illnesses include cancer, heart disease, and advanced stage Alzheimer's disease. Patients with terminal illnesses may receive palliative care, which aims to provide relief from pain and other distressing symptoms, allowing them to live as comfortably as possible during their remaining time.