My current project is broken down into 3 parts: Website, Desktop Client, and a Plug-in for a third party program. We had started out originally with Subversion for our source control but decided to try Mercurial after reading Joel Spolsky's final post. Considering we haven't really used the majority of svn's potential before, we figured starting fresh with some basic ideas of how source control worked would make this transition easy.

However, after setting up our initial repository, we're lost as to how tagging and branching should work on a project like this.

Essentially, we're working on all 3 of these parts at the same time. We want a release to be a combination of the 3 parts. Currently we're working in one repository.

For the Plug-in part, we have the first iteration finished which we've been referring to as Plug-In v0.1. For the first official build of the other two parts, we'd also like to refer to them as Website v0.1 and Desktop Client v0.1. When all three parts are at v0.1, we'd like to have a Full Project v0.1.

Our problem is we're not sure how to manage all of this in the Hg repository. Would the best way to handle this be to create 3 separate repositories for the 3 stable versions and then 3 more repositories for the current developments? Currently we have this all in one repository. Should we do this in branches (are branches any different from cloning repositories?) and tags?

Any help is greatly appreciated.