A Military dog tag is the informal name for the identification tags worn by military personnel, named such as it bears resemblance to actual dog tags. The tag is primarily used for the identification of dead and wounded and essential basic medical information for the treatment of the latter, such as blood type and history of inoculations, along with providing religious preference. Dog tags are usually fabricated from a corrosion-resistant metal or alloy such as aluminium, monel or stainless-steel, although, during wartime, they have been made from whatever metals were available. In the US military, if the member has a medical condition that requires special attention, an additional, red tag with the pertinent information is issued and worn with the dog tags.
Since the late 1990s, custom dog tags have become fashionable amongst musicians (particularly rappers), and as a marketing giveaway item. Numerous companies offer customers the opportunity to create their own personalized dog tags with their own photos, logos, and text. Even high-end jewelers have featured gold and silver dog tags encrusted with diamonds and other jewels. For example, to market the release of Call of Duty: Black Ops II, dog tags inscribed with the words "CALL OF DUTY BLACK OPS II" were given when a person pre-ordered the game.
A Pet dog tag, pet ID tag, or pet tag is a small flat tag worn on pets' collars or harnesses. Humane societies and rescue organizations recommend that dogs and cats wear these tags, which contain information to enable someone encountering a stray animal to contact the owner. Tags may make noise as animals move. A collar-mount tag, either slide-on or riveted-on, flat to a collar's surface, is silent and therefore eliminates the noise. A tag silencer encloses loose tags in a small neoprene pouch or a soft rubbery plastic ring around the edge of a tag and may reduce noise. The resemblance of human identification tags to this method of display led to military identification tags being called dog tags.