date in UNIX

1. To print system date and time in default format.
$ date

Sat Mar  9 18:09:06 UTC 2013

2. To print only system time
$ date +%T

18:09:26
 
3. To print only system date
$ date +%D

03/09/13
 
4. To print only year value
$ date +%Y

2013
 
5. To print only month name
$ date +%B

March