Marie Curie was born as Maria Sklodowska in Warsaw in Poland in 1867, as the fifth and youngest child to a teacher couple. The conditions could have been better – the family had lost its wealth due to poor investment, the oldest sister died when Marie was ten years old and modern two years later. But Marie already demonstrated a unique study ability as a child. After secondary school, she worked as a governor and auxiliary teacher, to finance the Bronislawa medicine studies in Paris. As a governor of a family called Zorawski, she fell in love with a son of the family, Kazimierz, a famous mathematician. One can only speculate in what ways her life had taken unless Zorawski’s family opposed marriage, something that Marie took very hard.But happiness turns. In 1891, it is time for Bronislawa to return the help she received when Maria moved to Paris to study physics, chemistry and mathematics at the Sorbonne. There she had famous teachers like PoincarĂ©, Appell and Lippman. In 1893 Maria took a degree in physics and the following year in mathematics. In the spring of 1894 she meets Pierre Curie and in the summer one year later they marry, marking the start of the most famous research couples found so far.She is known for the discovery of radiation and the elements Radium and Polonium for which she received the nobel prize in physics and chemistry.Marie Curie’s discovery of radium and polonium can be linked to her research on radioactivity alone. Polonium she discovered in 1898 when she did a study of radioactivity from the uranium mineral pech blend. Marie received the Nobel prize 1911 in chemistry for the discovery of the elements. She worked with her husband Pierre Curie to explore the radioactivity that was very new and relatively unknown at that time. With their research Marie and her husband discovered that radium secreted heat and emitted a radioactive gas and that radium salts were self-luminous. A mixture of radium salt and zinc sulfide was used for a while as a cover layer on the pointers in watches. This was done so you could see the time in the dark. Radium is used in nuclear power plants and in healthcare there it’s used as a source of radiation for the treatment of tumors. Polonium has contributed to the nuclear kernel’s discovery. Marie and her husband Pierre created a unit of measure of radioactive activity which they gave the name curie. For more than a hundred years, scientists, engineers and doctors have built on nuclear physics. It has given us both new knowledge and a lot of inventions.Some of them have been very good like devices for medical examinations and treatments.Some have not been particularly good like nuclear weapons. There are inventions that we do not really agree if they are good or not like the nuclear power.Important researchers in the 20th century are Henri Becquerel, Ernest Rutherford and Albert Einstein.We use radioactivity for example at medical examinations. Polonium is used as radiation and ionization source, p. a. in so-called activation analysis (jmf californium).Radium mixed with beryllium or boron uses radium to produce neutrons.