Locale (computer software)

In computing, a locale is a set of parameters that defines the user's language, region and any special variant preferences that the user wants to see in their user interface. Usually a locale identifier consists of at least a language identifier and a region identifier.

On POSIX platforms such as Unix, Linux and others, locale identifiers are defined by ISO 15897, which is similar to the BCP 47 definition of language tags, but the locale variant modifier is defined differently, and the character set is included as a part of the identifier. It is defined in this format: [language[_territory][.codeset][@modifier]]. (For example, Australian English using the UTF-8 encoding is en_AU.UTF-8.)

These settings usually include the following display (output) format settings:

The locale settings are about formatting output given a locale. So, the timezone information and daylight saving time are not usually part of the locale settings. Less usual is the input format setting, which is mostly defined on a per application basis.

Furthermore, the general settings usually include the keyboard layout setting.

In these environments,

and other (nowadays) Unicode-based environments, they are defined in a format similar to BCP 47. They are usually defined with just ISO 639 (language) and ISO 3166-1 alpha-2 (2-letter country) codes.

On POSIX platforms, locale identifiers are defined by ISO 15897, which is similar to the BCP 47 definition of language tags, but the locale variant modifier is defined differently, and the character set is included as a part of the identifier.

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