The body capable to do work is called energy. Energy has two kinds one is kinetic energy and other is potential energy. The energy in a body due to motion is kinetic energy for example moving car has kinetic energy and energy in a body due to height is potential energy for example energy in a hammer is potential energy.
Mechanical energy is the form in which energy present in a body due to both height and motion. For example energy in a car is mechanical. Heat energy is form of energy that transfers from hot body to cold body to maintain the temperature of both bodies. The energy comes from hot bodies is also heat. Heat is used to cook food and to keep our body temperature normal.
Sound energy is the form of energy produce by vibrating bodies like sound of drum produce when the surface of drum vibrates. Electrical energy is used at every place. Today it is not possible to live without electrical energy. Light energy is used to see things. It is also used for the process of photosynthesis. The main source of light energy is sun.
Every form of energy is converted into other form for example electrical energy is converted into mechanical and mechanical energy is converted into sound energy and other converted into other forms of energy.