security check issue

i140 approved and finger prints done at local uscis office as well 7 months ago, with 1-485 pending over a year already. got a notice from uscis which says sorry about the 1-485 delay, due to the security check. is there anyone can tell "security check", "background check", "name check" and "finger prints code 3" are the same thing or not? if not, what are they, respectively? which part will be done by FBI?
appreciate your explainations.
good luck to everybody,

所有跟帖： 

• 回複：security check issue -16073- ♀ (437 bytes) () 11/01/2005 postreply 10:32:03

• thank u 4 ur reply -136221- ♀ (25 bytes) () 11/01/2005 postreply 11:48:03

• 回複：security check issue -- ♀ (89 bytes) () 11/01/2005 postreply 18:28:47

• 回複：security check issue -1212- ♀ (89 bytes) () 11/01/2005 postreply 18:29:33