As you can see, locale names are system-dependent. Most systems, however, tend to follow the XPG (X/Open Portability Guide) naming convention, where a locale name has the following format:

language is the language name; territory is the territory name (a language can be spoken in different areas or countries: French, for example, is spoken in France, Canada, Belgium, Switzerland, and other countries); and encoding is a code set or an encoding method by which characters are coded.

The following examples show the format of a locale name as displayed on different UNIX systems. The locale is for French as spoken in France with the Latin1 encoding.

The following example shows the format of a locale on a Windows system. The locale is for French as spoken in France with Windows Code Page 1252.