Flash Powder is a powerful explosive used in many fireworks and pyrotechnic novelties. It is classified as a high explosive because when it is ignited or made to decompose into gas through some other means (such as electricity or percussion) it shatters everything around it because it explodes so quickly, not giving the adjacent items time to move out of the way, as is the property of Gunpowder. It, unlike Gunpowder, does not have the stability to propel a projectile. One of the main reasons that it has assumed the name of flash powder is that the aluminum, when ignited along with the rest of the mixture, burns with a brilliant white flash, similar to that of magnesium.
The main use of flash powder is in both safe, small firecrackers and M-80 style firecrackers. The illegal form of the M-80 contained about 3 grams of flash powder, enough to mutilate one's hand or even detach a finger or two. Legal forms contain considerably less than 1 gram per cracker.
The chemicals used in the more popular flash powders include 400 to 600 mesh Aluminum powder and Potassium Perchlorate as the essential ingredients. Barium Nitrate, Potassium Chlorate, Sulfur, Sodium Chlorate, and Potassium Permanganate, among other chemicals, are also used as oxidizers and fuels in flash powders. Specific formulas are widely available elsewhere, but it is also widely advised not to experiment with these hazardous compounds. Would I be right to assume that you enjoy the use of your hands?