HIV is the abbreviated form of Human Immuno-deficiency Virus. This virus causes Acquired Immuno Deficiency Syndrome or AIDS. Thus, HIV is the name of the virus and AIDS is the name of the disease. As the name AIDS implies, it is a condition where there is deficiency in the body's natural defence mechanism or the immune system. It is "acquired" because it is not a hereditary condition or due to long-term use of some medicines, such as those for treatment of cancer. Hereditary means conditions that are passed on from one generation to another. This means that AIDS is acquired because of certain behavioural patterns. Syndrome means a group of symptoms. When one gets AIDS, there can be a wide range of symptoms, all of which are due to the body’s diminished ability to fight diseases. It is important to remember that everyone who has HIV infection will develop IADS over a period of time depending upon their general health and natural defence mechanism of the body.