By default the short title, the long title or the column header of a data are recorded (on creation/update) in the connection language of the user.
It can be translated into an other language using the On line translation function (accessed via right click).
In the on line translation window of the active field you can add a language code and the translation in the corresponding language. A user logging in in one of the translated languages has available the short title, the long title or the column header in the login language (if this field is defined). If needed it is available in the default folder language.