HIV is simply the virus that causes AIDS while AIDS is the viral disease caused by HIV. HIV means Human Immunodeficiency Virus while AIDS means Acquired Immune Deficiency Syndrome. The virus that causes AIDS is a special one because it is not just a virus but a retro-virus that replicates in a fraction of seconds and attacks the human immune system severely. The immune system contains biological "soldiers" known as antibodies that fight against diseases. The weakening of the immune system makes the human body vulnerable to opportunistic infections including tuberculosis and HIV/AIDS. I suppose you know what I have just said about HIV/AIDS.
HIV/AIDS is transmitted through the exchange of blood directly or indirectly from an infected person to another person. The use of unsterilized sharp instruments such as a needle and injection syringe can cause the transmission of HIV/AIDS. Unprotected sexual intercourse can cause the transmission of HIV/AIDS. A mother living with HIV/AIDS can transmit to her unborn child through the umbilical cord which connects the mother and the unborn child. Blood transfusion can also lead to transmission of HIV/AIDS if the transfused blood is infected with HIV/AIDS. So there are only four known ways through which you can contact the virus that causes AIDS. There's no way you can contact HIV through mosquito bites, having a hand-shake with someone that is infected, hugging, kissing, and sharing personal effects such as towel and clothes with someone that is living with the virus.
The only way you can find out whether you have contacted the virus is through having a blood test. And you have to go for the blood test from time to time, at least twice in a year, because the virus has an incubation period of about 3-6 months. If you are not yet married abstinence from sexual intercourse is the best option for you but if you cannot abstain you have to protect yourself with a condom. Then if you are married you just have to be faithful to your partner - stick to him or her because he or she has got whatever you are looking for out there. You have to make sure that you avoid unprotected sexual intercourse, and other ways of getting infected with the disease.
But there is one thing you don't know about HIV/AIDS. What you don't know is that HIV/AIDS kills slower than the stigma attached to it by some people in our various societies. Yes, you heard well. Stigmatization has killed more people living with HIV/AIDS than the virus or the disease itself. Some people living with HIV/AIDS have been rejected by their families and friends simply because they tested positive to the virus. Some people living with the virus have lost their jobs simply because they are living with the virus. Some people have committed suicide because they thought they could not live to face the stigma. More and more people living with HIV/AIDS have died as a result of stigmatization or the psychological trauma that follows the disease.
You have to show love to these people living with HIV/AIDS. You have to show that their families and friends still want them. You have to show them that the society still wants them irrespective of the fact that they are living with HIV/AIDS. You have to let these people know that they are not less human because of their medical condition. You have to let them know that living with HIV/AIDS is not the end of the world. Let them know that they can still live a normal life though they are living with HIV/AIDS. As a matter of fact, anybody can live with the virus so you have no right to stigmatize anybody because of HIV/AIDS. If you wish to discuss about any specific problem, you can consult a doctor.