The document discusses key terms and concepts related to HIV/AIDS including: - AIDS is the final stage of HIV which weakens the immune system making one susceptible to opportunistic infections (OIs). - Common OIs seen in AIDS patients include Kaposi's sarcoma, Pneumocystis pneumonia, and AIDS-related complex (ARC). - Over 40 million people worldwide have AIDS, most in Africa, due to lack of access to treatment and cultural attitudes about sex.