A flare (or fusee) is described as a luminous device, that produces a brilliant light or intense heat without an explosion. Flares are used for signaling, illumination, or defensive countermeasures in civilian and military applications.
A firework is a pyrotechnic article containing explosive composition which, upon functioning, will burn or explode, or both, to produce a visual effect or aural effect, or both, and which is intended as a form of entertainment. Loose firework compositions, e.g. stars and powders are not included in this definition.
An explosive substance is a solid or liquid substance (or a mixture of substances) which is in itself capable by chemical reaction of producing gas at such a temperature and pressure and at such a speed as to cause damage to surroundings. Pyrotechnic substances are included even though they do not produce larges volumes of gases.
An endothermic reaction is one in which the products have more energy than the reactants, and thus a net input of energy, usually in the form of heat, is required. Endothermic reactions are often described as reactions that "feel cold", and contrast with exothermic reactions, in which heat is released.
An e-match or electrical igniter is an electrical device used to trigger pyro compounds, and is widely used in professional pyrotechnical displays.
They must be hooked up to an Electrical Firing Box (EFB).
Simple, an EFB is a type of remote switch that cause the flow of current trough the e-match resistor end the consequently heating up of the pyro compound.