The following outline is provided as an overview of and topical guide to energy:
Energy – in physics, this is an indirectly observed quantity often understood as the ability of a physical system to do work on other physical systems. [1] [2] Since work is defined as a force acting through a distance (a length of space), energy is always equivalent to the ability to exert force (a pull or a push) against an object that is moving along a definite path of certain length.
List of common units for energy. Official or common symbol in brackets after name and exact or approximate value of unit in joule in brackets after description.
See especially Category:Electric power and Category:Fuels for a large number of conventional energy related topics.