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).
Energy is only released when chemical bonds are formed. In general, a chemical reaction involves two steps: 1) the original chemical bonds between the atoms are broken, and 2) new bonds are formed. These two steps are sometimes lumped into one event for simplicity, but they are really two separate events.