Byte codified this common meaning. Many types of applications use information representable in eight or fewer bits and processor designers optimize for this common usage. The popularity of major commercial computing architectures has aided in the ubiquitous acceptance of the eight-bit size. Modern architectures typically use 32- or 64-bit words, built of four or eight bytes. The unit symbol for the byte was designated as the upper-case letter "B" by the International Electrotechnical Commission (IEC) and Institute of Electrical and Electronics Engineers (IEEE) in contrast to the bit, whose IEEE symbol is a lower-case "b". Internationally, the unit "octet", symbol "o",
Zero-byte file be zero bytes (a common convention terminates text files with a one- or two-byte newline, however). Conversely, zero-byte files must use some disk space to be indexed by a filesystem (though none for content, in most cases). In some cases, zero-byte files may be used to convey information like file metadata (for example, its filename may contain an instruction to a user viewing a directory listing such as documents-have-been-moved-to-partition-D, etc.); or to put in a directory to ensure that it is nonempty, since some tools such as backup and revision control software may ignore the empty directories. There are many