Active directory is the main part of 2003 server.The active 
directory installing the computer all host provide roming 
service.And user all information contain in the active 
directory

Active directory is a administrative tool .it handle all 
these object. such as  (user,grops, printers).

Active Directory is An Administrative tools
From which administrator can create ,manage users account
manage clients in the network can give restriction them 
with the help of group policy,can create users groups, ou's
to create a domain in the organisation u must have to 
install active direcroty services

Command:

DCPROMO

for removal

DCPROMO /FORCEREMOVAL

active directory is the directory service which contains of 
all user accounts information.

avtive directory is a directory which stores users accounts 
details and administrator handles the policies and 
permitions with the ad.administrator can restict to the 
users and groups.

ads is a win2003 servics.it is make database server of win 
2003.