The subsite group controls both user access to the subsite in iCM and the content the subsite itself can access.
Subsites are a view of the articles found in your iCM database. The access the subsite has to content is controlled by the permissions of its user group.
Group
Name
The unique name of the iCM group associated with the subsite. This name will be defaulted to the name of the subsite.
Group Description
A description of the iCM Group only ever displayed within iCM.
Permitted Templates
Use the "Select" button to select the templates that are allowed to be used on the subsite. You can change this later by editing the group iCM Content Roots.
User
This user is used by the subsite itself - it is not designed to be used by a human user to log into iCM. The user will automatically have full access to all of the content of this subsite.
You should give the user a valid email address and note down the password, but other than that it's best filed away somewhere safe and forgotten about.
How Content Roots Work - Sharing Content Between Subsites
As mentioned above, a subsite has a group and a user, usually named after the subsite. In our documentation for iCM 10.0.6.0, the subsite is called 10060, it has a user called 10060, which is in a group called 10060.
The 10060 user, just like any "human" iCM user, has access to some content in iCM, assigned via article content roots in the groups it is a member of.
This means that when someone visits the 10060 subsite URL, they'll only ever be able to see articles in the 10.0.6.0 article tree. Any other article ID or friendly URL, even if it exists on another subsite, will generate a page not found 404.
It's also possible to share content between subsites, allowing articles in a different article tree (or a completely different subsite) to appear as if they were part of the subsite a user is visiting.
To share content between subsites, add additional content roots to the group the subsite uses.
For example, if we wanted all of the articles in the "Shared Content Root" to be accessible on the iCM 10.0.6.0 URL, the root article of that tree is added to the 10060 iCM user group.
You'll still need a way to bring those articles into your navigation. Some of our website themes let you pick which articles appear in their main menu, or you could use the List template to display related content from the new content root.