Localization (L10N for short) is a process for adapting the software so that it is usable in a particular region; or a number of regions. Fuchsia has a workflow that allows program authors to equip their programs with language-specific resources (a.k.a localized assets).
At present, Fuchsia's localization support is limited, when compared to the scope of all localization features out there. However, even in its limited scope (though the scope will grow) enough small scale decisions have been made that it is useful to document them in the form of a specification.
This specification is by no means complete or final. We reserve the right to modify it in the future, and though we will make a best effort to evolve it in backward compatible ways, there may be cases in which breaking changes could be introduced if the benefits outweigh the potential downsides.