This review discusses the pathogenicity of bacteria and the challenges posed by antimicrobial resistance (AMR). Bacteria are classified into Gram-positive and Gram-negative based on their cell wall structure. Gram-positive bacteria have a thick peptidoglycan layer, while Gram-negative bacteria have a thin peptidoglycan layer and an outer membrane. Bacteria can be intracellular or extracellular, with intracellular bacteria living within host cells and extracellular bacteria existing outside. Pathogenic bacteria cause diseases by evading the host immune system through various mechanisms, including surface molecule modulation, antigenic variation, and subversion of phagocytic cells. AMR is a growing global health threat, with bacteria developing resistance to antibiotics through genetic transfer, mutations, and efflux pumps. The review highlights the importance of understanding bacterial pathogenesis to develop effective treatments and vaccines. It also emphasizes the need for improved antibiotic stewardship, new drug development, and a One Health approach to address the challenges of AMR. The study underscores the significance of host susceptibility, immune evasion, and the impact of bacterial infections on public health. The review concludes that a comprehensive strategy is needed to combat AMR, including better sanitation, responsible antibiotic use, and increased awareness of the consequences of antimicrobial resistance.This review discusses the pathogenicity of bacteria and the challenges posed by antimicrobial resistance (AMR). Bacteria are classified into Gram-positive and Gram-negative based on their cell wall structure. Gram-positive bacteria have a thick peptidoglycan layer, while Gram-negative bacteria have a thin peptidoglycan layer and an outer membrane. Bacteria can be intracellular or extracellular, with intracellular bacteria living within host cells and extracellular bacteria existing outside. Pathogenic bacteria cause diseases by evading the host immune system through various mechanisms, including surface molecule modulation, antigenic variation, and subversion of phagocytic cells. AMR is a growing global health threat, with bacteria developing resistance to antibiotics through genetic transfer, mutations, and efflux pumps. The review highlights the importance of understanding bacterial pathogenesis to develop effective treatments and vaccines. It also emphasizes the need for improved antibiotic stewardship, new drug development, and a One Health approach to address the challenges of AMR. The study underscores the significance of host susceptibility, immune evasion, and the impact of bacterial infections on public health. The review concludes that a comprehensive strategy is needed to combat AMR, including better sanitation, responsible antibiotic use, and increased awareness of the consequences of antimicrobial resistance.