What are three major malfunctions of ammunition?

Misfire: the hammer drops, but the primer never ignites Hangfire: the hammer drops, there is a noticable delay, then the cartridge fires Squib: the hammer drops and the the cartridge fires, but it sounds like a pop instead of a bang, normally resulting in a bullet being stuck in the barrel. Something similar can happen if a gun fires while out of battery, but this is technically not a squib.