This review provides an overview of antibiotic resistance (AR) mechanisms, with a focus on acquired resistance. It begins with an introduction to the discovery and mode of action of antibiotics, followed by a discussion of mobile genetic elements such as plasmids, transposons, and integrons, which are involved in the dispersal of antimicrobial resistance determinants between bacteria. The review covers various classes of antibiotics, including aminoglycosides, β-lactams, chloramphenicol, glycopeptides, macrolides, quinolones, streptothricin, sulfonamides, tetracyclines, and trimethoprim. For each class, the development of resistance is summarized along with the mechanisms of action. The review also discusses the resistance mechanisms and resistance genes involved in each class. The review highlights the increasing concern of antibiotic resistance, particularly in relation to resistant microorganisms, and the role of horizontal gene transfer in the spread of resistance. The review also discusses the role of mobile genetic elements in the acquisition and spread of resistance genes. The review concludes with a discussion of the importance of understanding and managing antibiotic resistance to prevent the spread of resistant microorganisms.This review provides an overview of antibiotic resistance (AR) mechanisms, with a focus on acquired resistance. It begins with an introduction to the discovery and mode of action of antibiotics, followed by a discussion of mobile genetic elements such as plasmids, transposons, and integrons, which are involved in the dispersal of antimicrobial resistance determinants between bacteria. The review covers various classes of antibiotics, including aminoglycosides, β-lactams, chloramphenicol, glycopeptides, macrolides, quinolones, streptothricin, sulfonamides, tetracyclines, and trimethoprim. For each class, the development of resistance is summarized along with the mechanisms of action. The review also discusses the resistance mechanisms and resistance genes involved in each class. The review highlights the increasing concern of antibiotic resistance, particularly in relation to resistant microorganisms, and the role of horizontal gene transfer in the spread of resistance. The review also discusses the role of mobile genetic elements in the acquisition and spread of resistance genes. The review concludes with a discussion of the importance of understanding and managing antibiotic resistance to prevent the spread of resistant microorganisms.