L20n is the codename code name for a localization architecture taking existing approaches one step further. The name stands for l10n 2. The architecture is laid out with Mozilla applications in mind, but should be applicable to other areas as well.Check out the [[L20n:FAQ]].
There are several localization-related communities out there, and thus there are different target audiences for docs on l10n (and l20n). In the order of appearance in the lifecycle of some code, that would be