Despite more than four decades of intense research and the remarkable success of combination antiretroviral therapy(cART) in suppressing viral replication, HIV infection remains incurable. The virus persists in a stochastic archipelago of long-lived cellular reservoirs that evade immune surveillance and therapeutic intervention, guaranteeing viral recrudescence upon treatment cessation. This fundamental paradox—effective suppression without eradication—represents the central impediment to a cure. In this review, we deconstruct the biological and immunological architecture of HIV persistence. We focus on the establishment and maintenance of latent reservoirs, the pharmacological blind spot of current therapies, and the conceptual frameworks that distinguish viral control from clearance. Decoding these mechanisms is an essential predicate for the rational design of next-generation curative strategies. Keywords : HIV persistence,HIV latency,Viral reservoir,HIV cure,Antiretroviral therapy,CD4+ memory T cells,Provirus,Immunological sanctuary,Clonal expansion,Functional cure,Shock and kill,Post-treatment control,Viral pathogenesis,Immunology,Infectious diseases