There are many forms of energy, light, thermal, gravitational, elastic, mechanical, electric, chemical, sound and nuclear. Every form of energy is correspondent to a type of energy.
Energy cannot be created or destroyed, it can only be transformed, for example, in a flashlight, chemical enegy from the batteries to mechanical energy for when the flashlight is being turned on then creates light and thermal energy. Kinetic and Potential energy are the only energy types.
Potential energy is stored inside a object like food, that when you eat it you obtain its energy, the human body obtains most of its energy from food. Kinetic energy is the energy of movement, for example when your turning on a stove, its kinetic energy. It starts of as chemical from the gasoline, mechanical when your turning it on and it becomes light/thermal energy.
It is important to know about energy because without any knowledge about energy we cant create or inovate technology, we wont be able to know what everything around us is and how it works.