date +FORMAT
where FORMAT is a combination of
%a locale's abbrev weekday name (Sun, Mon ...)
%A locale's full weekday name (Sunday, Monday ...)
%u day of the week (1..7, where 1=Monday)
%m 2 digit month
%d day of the month (01..31)
%e day of the month, blank padded (1..31)
%b locale's abbrev month name (Jan, Feb ...)
%B locale's full month name (January, February ..)
%C locale's century year (divide by 100 and truncate to integer 00-99)
%g 2 digit year
%G 4 digit year
%I hour (01..12)
%H hour (00..23)
%M minute (00..59)
%s seconds since epoch
%S seconds (0..60)
etc
eg. for 01 Jan 2008:-
date %d-%m-%G => 01-01-2008
date