Newbie: Working with Clients

Newbie: Working with Clients

I just signed up for an account yesterday, and I am new to project management in general. I'm a designer and I want to know if ZP is capable of what I need to do. I did search and I was able to find answers to some of my questions but some have not been answered.

What's the difference between USERS and CLIENTS? (I read a post on how to setup accounts for clients without the client doing all the work, but I just want some clarification on the difference between the two.)

Is it possible to set ZP so my clients can login and request work?

Is there a way to setup ZP so that all emails sent to a particular email account are also sent to ZP?

If any other "creatives" are using this to track projects, any helpful hints would be greatly appreciated!!!