HIV is a serious problem in worldwide which cause by lentivirus that leads to HIV infection and over time acquired immunodeficiency syndrome. AIDS is a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. AIDS is the most advanced stage of HIV and can only be diagnosed by a doctor. HIV is spread when an HIV-infected person's body fluids (blood, semen, fluids from the vagina or breast milk) enter another person’s bloodstream. The most common way people are infected with HIV is by having unprotected sex (vaginal, anal or oral). While having unprotected sex, the virus can enter the bloodstream through linings in the mouth, anus, sex organs (the penis and vagina), or through broken skin. Pregnant women with HIV can give the virus to their babies during pregnancy, childbirth or through breastfeeding. HIV can also be spread by sharing needles that are used for taking drugs (legal and illegal), tattooing, and piercing. Both men and women can spread HIV. A person with HIV can feel okay and still give the virus to others.