Dragons are a newly developed weapon originally designed by the Illuminator Aludra. She initially creates them as a means of taking revenge on the Seanchan for destroying the Illuminator's Guild. Mat Cauthon proposes the weapon to Elayne Trakand in Caemlyn who agrees to lend every bellfounder in Andor in order to make them.
Dragons are a parallel to real-world cannons. They appear to be shaped like a bell, albeit they are very long and in proportion, slender. Using a similar kind of powder as are used in making fireworks, the projectile - dubbed "dragon's egg" - is fired from the dragon with the light of a torch.
Dragons can fire up to one mile, and their effects are devastating. They are able to take out entire hillsides with a single blow. The result is compared to the destructive powers of damane, making the dragons very advantageous, as they do not require the One Power.
Aludra also designed a separating shot that would cause lesser overall damage, but be able to hit in a much wider range per shot. These are the same thing as canister shot used in real-world cannons.