How do you uses AD Distinguished Names

Your question is very broad and general, being more specific would help.

Anyway, DN is an unique id. Can be a user id, host id , etc depending on the schema.

Win2k use users DN for logon and authentication.
For example, your administrator's username would look something like this in DN form.

cn=administrator,cn=users,dc=foo,dc.com

for the domain foo.com.

ADS, essentially a ldap, you can use ldap command to view, add or modify object.

eg to match all object for the user tree,

ldapsearch -b "cn=users,dc=foo,dc=com" -D "cn=administrator,cn=users,dc=foo,dc.com" -w [Administrator password] "object=*"

They are a lot of practical ways to use DN, one obvious one is single sign on and integration with other ldap enable product. As for showing you how all this work .... the area is too broad .. u need to be specific

The anwser is all your question is no, on the basis that you are assuming DN, which is just a unique id, could be use like a command.

As I mention earlier, AD is an ldap, and ldap is just a database storing information about things like, printer setting/location, host information, user information, mail routing/hosting information, even DNS information and etc.

And DN is like a unique key to access these info. As mention earlier you need tools to access the ldap and use the infomation attached to the DN.

For example, you can write a script, access the info about a particular printer using DN of the printer. Then use the infomation about the printer to automatically map the printer on a particular pc. As for whether it will be tranparent or not, that will depend on your implementation.