Examples of heat energy include electrical stoves, hairdryers, a just-sharpened pencil and sun rays. Heat, or thermal energy, is typically converted from mechanical, electrical or chemical energy.
The earth and its inhabitants are made up of energy, atoms and molecules. Atoms and molecules are constantly in motion, and when they bump into each other, the collisions create heat energy, which is present in all matter. When molecules move faster, and the number of collisions between them increases, heat energy increases as well. A common example is rubbing a pencil quickly between two hands or sharpening a pencil. This motion causes the pencil to become warm or even hot.