How do we use nuclear energy?
We use nuclear energy in a few different ways, but the main two are to generate electricity and to build nuclear weapons.
Electricity
Nuclear energy is used to generate electricity because it's one of the cleanest energy souces and if everything works correctly it has a low impact on the environment. Nuclear energy does not create green house gases so is seen as a good alternative to burning fossil fuels. However, there is argument over the risk of radiation from nuclear power plants if there is an accident. (Look at the link 'How does nuclear energy affect the environment' to find out more).
In March 2011, there were 443 operating nuclear power reactors spread across 47 different countries. In 2009 nuclear energy accounted for 14 percent of the world's electricity production, but in individual countries the percentage is much higher for example in France where 75.2 % of electricity is produced by nuclear power plants. In the United States over 100 nuclear reactors supply about 20% of the country's electricity.
Nuclear weapons
A nuclear weapon is a device that derives its destructive force from nuclear reactions either fission or a combination of fission and fusion.
Since their first use in 1945, nuclear bombs have been the most dangerous weapons of mass destruction used by man. Nuclear bombs can destroy property and emit radiation that can kill hundreds of thousands of people.
Other uses
There are other ways we use nuclear energy for example, nuclear medicine which involves the use of radioactive materials in the diagnosis and treatment of various diseases.