[Trac] Are project environments independent and separate

[Tony DeYoung]

Trac looks great. But one question before I set it up:

Are project environments completely separate from each other?

So for example, if I have two groups of coders, can I create  
environments for each and set permissions so that only users in group  
A have access to Wiki and Roadmaps for Project A,  and only users in  
group B have access to Wiki and Roadmaps for Project B.
So basically each group has their own private wiki, roadmaps and  
ticketing system?

If so, is there any limit to the number of projects I can create?

Thanks