A cage is an enclosure often made of mesh, bars, or wires, used to confine, contain or protect something or someone. A cage can serve many purposes, including keeping an animal or person in captivity, capturing an animal or person, and displaying an animal at a zoo.Zoo cageAviaryDecorative aviaryBattery cageHamster or mouse cageRat cageRabbit cageThe hand of a marmoset caged at a butterfly parkCage of bird trapper (late nineteenth century)Birdcage (eighteenth / nineteenth century)Cage protecting a baptismal fontLocker cages in Hong KongProtection cageSharks around a shark cage being used for shark tourismFaraday cageGo-go dancing cage A cage is an enclosure often made of mesh, bars, or wires, used to confine, contain or protect something or someone. A cage can serve many purposes, including keeping an animal or person in captivity, capturing an animal or person, and displaying an animal at a zoo.