Energy: the ability to do work
Every movement we make requires energy. There are six forms of energy.
Chemical Energy: energy that stores within the bonds
Mechanical Energy: energy of a moving object
Thermal Energy: energy of the motion of molecules (or heat energy)
Radiation Energy: energy of lights, electromagnetic waves
Electrical Energy: energy of the movement of electrons
Nuclear Energy: energy stored within the nucleus of an atom
In our daily life basis, energy had converted from one form to another; because according to the laws of thermodynamics, energy cannot be created or destroyed.
In this image, it shows that a girl is cycling. The peddling produces thermal energy and mechanical energy. The mechanical energy is then converted into electrical energy to heat up the water. Which the boiling water then produces thermal energy.