The one-to-one correspondence between punched hole patterns and the bit patterns by which codes are represented, with special reference to the UK 7-bit data code specified in BS 4730; in appendices, illustrations of the UK 7-bit data code represented on 1 in paper tape with EVEN parity and of ITA No. 2 (Telex code) and a typical 4-bit code represented on 11/16 in paper tape without row parity.Cross References:BS 3880:Part 1BS 3880:Part 2BS 3880:Part 4BS 4730BS 4731:Part 1BS 4953ISO 646ISO 2022