A explosive is a substance or device capable of producing a volume of rapidly expanding gas that exerts sudden pressure on it's surroundings. Basically there are two types of explosives. The difference here is that detonating explosives like TNT and Dynamite are characterized by rapid decomposition and high pressure, wheras deflagrating explosives lik black powder merely burn rapidly and create low pressures. However as we all know black powder under certain conditions will detonate for example if we pack it into a enclosed area such as a pipe or Co2 cannister. Now the detonating explosives are divided into two types primary and secondary.
Primary explosives detonate by ignition i.e. a flame, spark, impact, or other means of heat.
Secondary explosives require a detonator and occassionally a secondary booster. Now those are the basics, which should be remembered and marked, as those terms will come back to haunt you. Now I am about to teach you how to make an excellent quality gunpowder. This is just short of factory 7FA po, which is the best. Experiment on your own and find out which ratios work best for you.