World AIDS Day, designated on 1 December every year since 1988, is an international day dedicated to raising awareness of the AIDS pandemic caused by the spread of HIV infection and mourning those who've died of the disease. The acquired immunodeficiency syndrome (AIDS) is a life-threatening condition caused by the human immunodeficiency virus (HIV). The HIV virus attacks the immune system of the patient and reduces its resistance to other diseases. Government and health officials, non-governmental organizations, and individuals around the world observe the day, often with education on AIDS prevention and control.

HIV prevention refers to practices that aim to prevent the spread of the human immunodeficiency virus (HIV). HIV prevention practices may be undertaken by individuals to protect their own health and the health of those in their community, or may be instituted by governments and community-based organizations as public health policies.