HIV is transmitted as Lizzie Lou stated.
Unprotected vaginal and anal sex
Sharing works with other IV drug abusers
Mother to child.
This is what i get from http://www.aidshotline.org/
How is HIV transmitted?
HIV can be transmitted from an infected person to another through:
Blood (including menstrual blood)
Semen
Vaginal secretions
Breast milk (risky only to infants)
Mother to Child: Mother to child transmission is now rare in the US and other developed countries because pregnant women who are HIV+ are normally given medications to prevent the fetus from getting infected. However, it is possible for an HIV-infected mother to pass the virus directly before or during birth, or through breast milk. Breast milk contains HIV, and while small amounts of breast milk do not pose significant threat of infection to adults, it is a viable means of transmission to infants.
hiv is transmitted by through...
unprotected vaginal/anal intercourse
sharing iv drug works
mother to child