Factory pattern should be used when: - a framework delegate the creation of objects derived from a common superclass to the factory - we need flexibility in adding new types of objects that must be created by the class. Along with singleton pattern the factory is one of the most used patterns.
In thermodynamics, the term exothermic process (exo- : outside) describes a process or reaction that releases energy from the system to its surroundings, usually in the form of heat, but also in a form of light (e.g. a spark, flame, or flash), electricity (e.g. a battery), or sound (e.g. explosion heard when burning hydrogen).
An exothermic reaction is a chemical or physical reaction that releases heat. It gives net energy to its surroundings. That is, the energy needed to initiate the reaction is less than the energy that is subsequently released. When the medium in which the reaction is taking place gains heat, the reaction is exothermic.