[K12OSN] LDAP is for?

[Huck]

What is the benefit of using LDAP with SAMBA instead of just using plain 
old SAMBA
and making it the primary domain controller for XP machines to login to?

I would only need to
'adduser <username>'
'smbuser <username>'
'passwd <username>'
'smbpasswd <username>'

and I'd be golden ya, students would logon to their XP machines(in 1 
lab) with their samba username...
and authenticate to the domain via samba and have access to their /home 
directories...

What is it that LDAP is doing ?  I'm not sure if I need LDAP or not...

--Huck