This system environment variable controls the formatting of dates and times. By default, Managers use time and date formats that are sensitive to locale settings. For example, if you chose a date format that includes the name of the day of the week, in the English locale, the first weekday is formatted as Monday, while in the French locale it is formatted as Lundi.
If LC_TIME is not set, the system variable LC_ALL is used. If LC_ALL is not set either, the system variable LANG is used. Finally, if LANG is not set, a default “C locale” (essentially US English) is used.
The locale names and available locales are system specific.