hexd prints a human-readable hexdump of the specified files, or standard input if omitted. Its main distinguishing feature is the use of colours to visually indicate which range of values an octet belongs to, aiding in spotting patterns in binary data. By default, hexd relies on 256-color SGR escape sequences. Most terminal emulators should support these today, but technically they're only defacto standard. However, you can override the formatting used with the HEXD_COLORS environment variable (see manpage), or use the -p option for plaintext output.