Man has known since ancient times energy, its sources, forms, transformations and uses in a way that is accessible to him in order to facilitate the affairs of his daily life.

Energy forms:

There are many forms of energy that man has known since the beginning of creation and used it to serve him, and the most important forms of energy are the following:

• Mechanical energy associated with objects: divided into kinetic energy resulting from the movement of the body, and potential energy stored in the body; As a result of being in a position.
• Electrical energy resulting from the transfer of negative charges from one end to the other: it is divided into transition energy and static energy.
• Thermal energy arising from the transfer of heat from one body to another: is transmitted by radiation, convection, or direct contact.
• Chemical energy arising from the release of the energy potential in chemical bonds: it is formed as a result of it being broken to form new bonds during a chemical reaction.
• Nuclear energy arising from the fission of the atom and its components.
• Hydropower or tidal energy: It is created by the movement of water and collision with the surrounding rocks and is used to generate electricity.
• Light energy from light-emitting objects such as the sun.

Energy Transformations:

 One of the characteristics of energy is its ability to transform from one form to another, and this is among the definition of energy that it is like matter that does not perish or be created from scratch, but transforms from one form to another, and among the most prominent of its transformations are:

• Electromagnetic and electrical energy → sound and light energy in television and radio.
• Chemical energy in automotive fuels → Kinetic and thermal energy.
• Electric energy in a fan → kinetic energy.
• Light energy from the sun → Chemical energy during the photosynthesis of plants.
• Electrical energy in the heater → Thermal energy.
• Chemical Energy in Gas Heater → Thermal Energy.
• The potential energy of an object in free fall → kinetic energy.
• Thermal and light energy emitted from the sun → electrical energy as in solar panels.