Full Forms and Definitions:STD – Sexually Transmitted Disease: Diseases spread via sexual contact (gonorrhea, syphilis).STI – Sexually Transmitted Infection: Infections from sexual activity, including bacteria, viruses, parasites.HIV – Human Immunodeficiency Virus: Attacks the immune system, leading to AIDS if untreated.HPV – Human Papillomavirus: Virus group causing genital warts and cervical cancer.AIDS – Acquired Immune Deficiency Syndrome: Final stage of HIV with very weak immunity.