Radioactive isotopes are atoms that have an unstable nucleus and emit radiation as a result of their instability. These isotopes can be used in various fields of research, including medicine, industry, and environmental studies. In medicine, radioactive isotopes are commonly used in diagnostic imaging, cancer treatment, and therapy. In industry, radioactive isotopes are used for quality control, manufacturing, and material testing. In environmental studies, radioactive isotopes can be used to track the movement of substances in natural systems and understand geological processes. Overall, radioactive isotopes play a crucial role in advancing scientific research and technology across a range of disciplines.