HIV/AIDS is usually passed by having sex without a condom with a person who has HIV/AIDS. The best way to protect yourself from it is to abstain or use a condom EVERY TIME you have sex. You can get HIV/AIDS if infected body fluids like blood get into a cut/wound/under fingernails, or if you are cut with infected sharp instruments like needles. To prevent getting HIV/AIDS through cuts use clean instruments and health workers must wear gloves. HIV can also be passed from mother to child during labour/breastfeeding. A program called PMTCT can prevent this.
Attribution: Marie Stopes