Schemas Vs DTDs

HI All,

I am a newbie in XML .

I need some info abt schemas and DTDs

What should be preferred amongst Schema and DTD while using XML.

I know that there are a few added advantages abt Schemas such as

1. they have open content model which allows us to add more elements and / or attribuites

2. u can specify datatypes for the elements or the attributes ..

3. u can have namespaces for ur schemas

and a few more..

but I don't have any solid argument as to why schema or DTD is used.

Can anyone pl tell me what should be preferred or is there any standard practice to use only DTDs ..

coz from all the previous mails that i have received from this mailing list ..i have only seen people using DTDs.

Regards,

Amol