EBS-R12- Default users

Does anyone know what these users mean and when & how are these get created in EBS?  Is it safe to delete them?
R12.1.2- Module CN - SALES & Marketing.

!AUSTINPRODUCTION    10/16/2010
!CNRCAMADMIN    10/19/2010
!DALLASPRODUCTION    10/16/2010
!DOLBY    10/16/2010
!KCPRODUCTION    10/18/2010
!LINCOLNPRODUCTION    10/16/2010
!NTXCSGPWRESET    10/18/2010
!SERVERADMIN    10/16/2010
!SWROCADMIN    10/16/2010
!TXCHECOMSVR    10/18/2010
!TXCHEPTHSVC    10/18/2010
!TXCHERPTSVC    10/16/2010
!TXCHESQLSVC    10/16/2010
!TXCHEWOSCAN    10/16/2010
!TXDALMINTEK    10/16/2010
!TXDALMSIDATA    10/16/2010
!TXDALQUOTA    10/18/2010
!TXDALREPOSITORY    10/18/2010
!TXDALRPTTEAM    10/16/2010
!TXDALSWUSR    10/16/2010
!TXDALVERITAS    10/18/2010
!TXDALWEBSENSE    10/18/2010
!TXDESIGNSCAN    10/19/2010
!TXKINGOVAFF    10/18/2010
!TXKININET    10/18/2010
!TXROYCDR    10/16/2010
!TXROYLHSESVR    10/18/2010
!TXROYNICE    10/18/2010
!TXROYREALSOFT    10/16/2010
!TXROYRTA    10/16/2010
!TXROYSLING    10/18/2010
!TXROYTELGEN    10/18/2010
!TXROYTEST001    10/16/2010
!TXROYWITNESS    10/18/2010
!WACOPRODUCTION    10/18/2010
$A0B500-S9I9TQE1MR98    10/16/2010
$DUPLICATE-54D41    10/15/2010
$DUPLICATE-588E7    10/15/2010
$DUPLICATE-6099F    10/15/2010
$DUPLICATE-74875    10/15/2010
$DUPLICATE-7869B    10/15/2010
$DUPLICATE-7F78E    10/15/2010
$DUPLICATE-7F78F    10/15/2010
$DUPLICATE-7F7A9    10/15/2010
$DUPLICATE-7F8AE    10/15/2010
$DUPLICATE-8943B    10/15/2010
$DUPLICATE-894BA    10/15/2010
$DUPLICATE-89508    10/15/2010
$DUPLICATE-8CCAE    10/15/2010
$DUPLICATE-8CCB0    10/15/2010