Each additional language comes with an added overhead for maintenance.
Languages can be set for country specific, or generic. For example, Dutch is offered in these variations:
Dutch (Belgium)
Dutch (Netherlands)
Dutch
The system will always use the country-specific translation if possible, but will always fall back to the generic "base" language if there is no translation for a user’s country-specific locality.
Step 1, add the required language(s).
Log into the web application as an Admin User
From the menu, select Designer Languages Maintain Languages
Select New
Search for the required Language, and save
Repeat the above steps until you have added all the required languages
As a next step, you must add Localities, as outlined below
IMPORTANT:
To apply locality specific formatting to Date and Decimal Fields, it is required to add the corresponding Language before creating the Locality.
Languages 
