Pistols, Rifles, Shotguns, Hammers, and Swords. Depending on what you kill and how many kills you have on the weapon it will change it's appearance and stats accordingly. For example, you have a sword with whch you've killed 100 Hollow men. The hilt of the sword would become bone, and if you kill civilians the blade might drip blood. There will also be gauntlets for Will powers.
Due to various looks and levels of weapons some will resemble other items such as hammers might look like axes and rifles like snipers or shotguns based on style.