The article provides an overview of acquired antibiotic resistance genes, detailing the history, mechanisms of action, and resistance mechanisms for various classes of antibiotics. It highlights the emergence of resistance in bacteria to aminoglycosides, β-lactams, chloramphenicol, glycopeptides, macrolide-lincosamide-streptogramin B, quinolones, streptothricin, sulfonamides, tetracyclines, and trimethoprim. The mechanisms of resistance include changes in permeability, altered ribosome structure, inactivation by enzymes, and the production of β-lactamases. The article also discusses the role of mobile genetic elements, such as plasmids and integrative conjugative elements (ICE), in the horizontal transfer of resistance genes. The increasing prevalence of resistance and the challenges posed by these mechanisms are emphasized, along with the need for continued research and surveillance to combat the growing threat of antibiotic resistance.The article provides an overview of acquired antibiotic resistance genes, detailing the history, mechanisms of action, and resistance mechanisms for various classes of antibiotics. It highlights the emergence of resistance in bacteria to aminoglycosides, β-lactams, chloramphenicol, glycopeptides, macrolide-lincosamide-streptogramin B, quinolones, streptothricin, sulfonamides, tetracyclines, and trimethoprim. The mechanisms of resistance include changes in permeability, altered ribosome structure, inactivation by enzymes, and the production of β-lactamases. The article also discusses the role of mobile genetic elements, such as plasmids and integrative conjugative elements (ICE), in the horizontal transfer of resistance genes. The increasing prevalence of resistance and the challenges posed by these mechanisms are emphasized, along with the need for continued research and surveillance to combat the growing threat of antibiotic resistance.