Biosensors are widely used in biomedical diagnosis and various other fields such as point-of-care monitoring, environmental monitoring, food control, drug discovery, and biomedical research. They are devices that measure biological or chemical reactions by generating signals proportional to the concentration of an analyte. A biosensor typically consists of an analyte, a bioreceptor, a transducer, and electronics, with the display providing the final output. The bioreceptor is a molecule that specifically recognizes the analyte, and the transducer converts the bio-recognition event into a measurable signal. The electronics process the transduced signal and prepare it for display. The history of biosensors dates back to the early 20th century, with the first true biosensor developed by Leland C. Clark in 1956 for oxygen detection. Since then, biosensors have evolved significantly, with the development of the i-STAT sensor marking a major advancement. Biosensors are now a multidisciplinary field that combines principles from basic sciences, micro/nano-technology, electronics, and medicine. They have a wide range of applications, including disease detection, food safety, defense, and drug discovery. Biosensors can be used for both single-shot analysis and long-term monitoring. Nanotechnology has had a major impact on biosensing technology, enabling the development of more sensitive and selective biosensors. The integration of nanomaterials such as graphene and carbon nanotubes has improved the performance of biosensors, allowing for the detection of single molecules. Biosensors are also used in various applications, including pregnancy tests, glucose monitoring, and environmental monitoring. Despite their widespread use, biosensors face challenges in commercialization, including difficulties in translating academic research into commercially viable prototypes and regulatory issues. However, recent advancements in translational research and interdisciplinary collaboration have led to significant progress in biosensor technology. Biosensors are now an important part of society, improving quality of life in various areas such as healthcare, agriculture, and environmental monitoring.Biosensors are widely used in biomedical diagnosis and various other fields such as point-of-care monitoring, environmental monitoring, food control, drug discovery, and biomedical research. They are devices that measure biological or chemical reactions by generating signals proportional to the concentration of an analyte. A biosensor typically consists of an analyte, a bioreceptor, a transducer, and electronics, with the display providing the final output. The bioreceptor is a molecule that specifically recognizes the analyte, and the transducer converts the bio-recognition event into a measurable signal. The electronics process the transduced signal and prepare it for display. The history of biosensors dates back to the early 20th century, with the first true biosensor developed by Leland C. Clark in 1956 for oxygen detection. Since then, biosensors have evolved significantly, with the development of the i-STAT sensor marking a major advancement. Biosensors are now a multidisciplinary field that combines principles from basic sciences, micro/nano-technology, electronics, and medicine. They have a wide range of applications, including disease detection, food safety, defense, and drug discovery. Biosensors can be used for both single-shot analysis and long-term monitoring. Nanotechnology has had a major impact on biosensing technology, enabling the development of more sensitive and selective biosensors. The integration of nanomaterials such as graphene and carbon nanotubes has improved the performance of biosensors, allowing for the detection of single molecules. Biosensors are also used in various applications, including pregnancy tests, glucose monitoring, and environmental monitoring. Despite their widespread use, biosensors face challenges in commercialization, including difficulties in translating academic research into commercially viable prototypes and regulatory issues. However, recent advancements in translational research and interdisciplinary collaboration have led to significant progress in biosensor technology. Biosensors are now an important part of society, improving quality of life in various areas such as healthcare, agriculture, and environmental monitoring.