HIV stands for Human Immunodeficiency Virus.
Human immunodeficiency virus (HIV) causes acquired immunodeficiency syndrome (AIDS). A positive HIV test result does not mean that a person has AIDS. Most people with HIV look and feel healthy for a long time, so you can't tell who has the virus just by looking at them. However, the virus slowly damages  the person's immune system.

This means, they are less able to resist and recover from infections. Eventually the person will get infections or illnesses that do not usually affect people with healthy immune system. A person has AIDS when one of these illnesses occur.

There are three main ways to get HIV:

By having vaginal, anal or oral sex without a condom with someone who has HIV.
By using needles, syringes or other drug injecting or tattooing equipment that is infected with HIV.From a woman with HIV to her baby (before or during birth) and by breastfeeding.

HIV can be diagnosed by a simple blood test, which checks your blood for antibodies to HIV.

There is neither a cure for AIDS, nor a vaccine for HIV. Although anti-retroviral drugs have been developed, which
mean that some people can stay well for longer. As with other diseases, early detection provides more options for treatment and preventative care.