What are the sources of energy?

There are six basic kinds of energy. As you throw a basketball, your arms give it mechanical energy in the form of movement. A burning log gives off chemical energy, which you can see as light and feel as heat. A hot burner on the stove receives electrical energy from an outlet and supplies thermal energy to a frying pan with eggs. The sun sends radiant energy to Earth every day in the form of light but gets its own nuclear energy from reactions inside the nuclei of its own atoms. Nuclear energy can be produced in two ways. In the sun, energy is created by the joining of the nuclei of hydrogen atoms in a process called fusion. On Earth the nuclei of larger atoms such as uranium split apart to create energy in a process called fission. All types of energy are essentially different forms of one another.

Source:http://www.cameco.com/uranium_101/fact.php#two
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