Refers to the use of more than one (natural) language. This does not refer to the use of multiple programming languages.
Multilingualisation (or "m17n", where "17" stands for 17 omitted letters) of computer systems can be considered part of a continuum between internationalization and localization:
- A localised system has been adapted or converted for a particular locale (other than the one it was originally developed for), including the language of the user interface, input, and display, and features such as time/date display and currency; but each instance of the system only supports a single locale.
- Multilingualised software supports multiple languages for display and input simultaneously, but generally has a single user interface language. Support for other locale features like time, date, number and currency formats may vary as the system tends towards full internationalisation. Generally a multilingualised system is intended for use in a specific locale, whilst allowing for multilingual content.
- An internationalised system is equipped for use in a range of locales, allowing for the co-existence of several languages and character sets in user interfaces and displays. In particular, a system may not be considered internationalised in the fullest sense unless the interface language is selectable by the user at runtime.