Plasmids are self-replicating genetic elements that can confer antimicrobial resistance in bacteria. They are classified into incompatibility groups based on their replication systems and are crucial in the spread of resistance genes. The IncF, IncA/C, IncL/M, and IncI plasmids are among the most prevalent in Enterobacteriaceae, often carrying genes for extended-spectrum beta-lactamases (ESBLs), AmpC beta-lactamases, carbapenemases, and other resistance mechanisms. The spread of these plasmids is influenced by factors such as antimicrobial use and horizontal gene transfer. The IncF plasmid family, for example, is associated with the blaCTX-M-15 gene, which is a major cause of antibiotic resistance in clinical isolates. Other plasmid families, such as IncN and IncHI2, are also involved in the dissemination of resistance genes. The identification and classification of plasmids are essential for understanding their role in the spread of resistance and for developing strategies to combat drug-resistant bacteria. Techniques such as PCR-based replicon typing (PBRT) and whole-genome sequencing are used to characterize plasmids and identify their resistance determinants. The diversity of plasmid families and their ability to adapt and spread highlight the complexity of antimicrobial resistance in Enterobacteriaceae. Understanding the mechanisms of plasmid transmission and the factors that drive their spread is crucial for developing effective interventions to reduce the global burden of antibiotic resistance.Plasmids are self-replicating genetic elements that can confer antimicrobial resistance in bacteria. They are classified into incompatibility groups based on their replication systems and are crucial in the spread of resistance genes. The IncF, IncA/C, IncL/M, and IncI plasmids are among the most prevalent in Enterobacteriaceae, often carrying genes for extended-spectrum beta-lactamases (ESBLs), AmpC beta-lactamases, carbapenemases, and other resistance mechanisms. The spread of these plasmids is influenced by factors such as antimicrobial use and horizontal gene transfer. The IncF plasmid family, for example, is associated with the blaCTX-M-15 gene, which is a major cause of antibiotic resistance in clinical isolates. Other plasmid families, such as IncN and IncHI2, are also involved in the dissemination of resistance genes. The identification and classification of plasmids are essential for understanding their role in the spread of resistance and for developing strategies to combat drug-resistant bacteria. Techniques such as PCR-based replicon typing (PBRT) and whole-genome sequencing are used to characterize plasmids and identify their resistance determinants. The diversity of plasmid families and their ability to adapt and spread highlight the complexity of antimicrobial resistance in Enterobacteriaceae. Understanding the mechanisms of plasmid transmission and the factors that drive their spread is crucial for developing effective interventions to reduce the global burden of antibiotic resistance.