ER Question

[Samuel A. Mullen]

I've never really created any sort of information diagram using a tool
other than pen and paper, so this may be a dumb question.

The ER diagram section in DIA, is it for designing physical database
models?  If so, should the entities hold information concerning tables?

If I'm using the wrong tab, please let me know. 

Thanks,
Sam

ps - From what I've seen, this is a really great tool.