Krypton is one of the rarest gases in the atmosphere and it is odorless, colorless, and tasteless. Krypton is used to fill electric lamp bulbs which are filled with a mixture of krypton and argon, and for various electronic devices. Krypton is also used in photographic projection lamps, in very high-powered electric arc lights used at airports and in some strobo-lamps, because it has an extremely fast response to an electric current.