Isotopes are atoms of an element that have the same amount of protons, but have less or more neutrons. They are a variation of an element which has the same atomic number but different mass number. Radioactive isotopes are isotopes that have an unstable nucleus, making the the isotope emit radiation. This radiation can be emitted by Alpha particles, Beta particles or by Gamma rays. Radioactive isotopes can be of great use, as we can use the energy they radiate. As the isotopes radioactivity is easy to detect, radioactive isotopes can be good tracers. When one atom or more in a substance is replaced by radioactive isotopes, it can then be tracked and monitored by their emissions, this are called radioactive tracers. This is used to follow the paths of biochemical reactions or to determine how a substance is distributed within an organism. In medicine, radioactive tracers can be used for both diagnosis and treatment, and environmentally, radioactive tracers are used to measure engine wear, analyze the geological formation around oil wells and other similar things.The impact radioactive isotopes have had on medicine has been revolutionary. There are over 10 million procedures that use radioactive isotopes that facilitate the doctors live and give a proper treatment to patients. Some of the most famous treatments with radioactive isotopes in medicine are, the gamma ray irradiation of tumors, that uses isotope 60Co, and the cancer detection and treatment that uses isotope 32p. Radioactive isotopes are also used for PET (positron emission tomography), in where the patient ingest a positron emitting isotope which travel through the body to certain parts, so when the person enters in the machine the gamma radiation of the positron is detected and it can take a more detailed image of the specific parts for doctors to analyse easier and better.Radioactive isotopes are also found in your daily day. Isotope Americium-241, is an emitter used in tiny amounts for smoke detectors. Am-241 radiates an emission that ionize the air between two electrode plates in of the chamber. A battery supplies a power source that causes movement of the ions, making them create a small electric current. So when smoke enters the chamber, the movement of the ions is interrupted by slowing down, reducing the conductivity of the air. This causes a drop in the current, that triggers an alarm. In the food industry the radioactive isotope is used to kill any microorganism that may grow in the food. Food for not to be poisonous or harmful when eaten, food has to be treated. Food goes through a process of irradiation, usually with the radioactive isotope of Cobalt-60. In this way, food is not only cleaned up and prevented from illnesses but also now food stays fresh for longer time.So in conclusion radioactive isotopes are tracking tool that give exceptional abilities. It has immensely helped medicine to advance making various procedures easier and more effective, have facilitated on some industrial products making them also easier and safer, and has helped the food industry make a much healthier, safier and longer products for people.