Daggers are items added by Better Dungeons. They can be crafted and come in a variety of material types.
Daggers are, as one would imagine, weaker than their sword counterparts of the same material. Both are seeming to have nearly the same damage output as a stone (For iron) and iron (For diamond) swords, albeit more durable, respectively. You cannot make a Better Dungeon dagger out of wood or stone. Most weapons have a much higher damage output, and daggers are mainly more for asthetic purposes or roleplaying situations (Such as if there was some type of ritual sacrifice or a cult on a server.) when a lot more players favor their larger cousins for longer expeditions into the wild unknown to protect themselves from the many dangers that lurk in the shadows.
It acts exactly like a vanilla sword, if only shorter. Holding right click (Or whatever you have Use bound to) will hold up the dagger in front of you, halving the damage recieved from the front.
Daggers are commonly found in chests of most Better Dungeons mod dungeons.
A dagger from the Better Dungeons mod can be place onto a Sword Pedestal, but it will float above the pedestal vertically. This is because it bases the sword pommel at the same point every time for any weapon, and the blade is much shorter than other weapons.