There is no Software inventory.
Hardware inventory is performed either through the deployment/capture process of a registered machine, or via a dedicated Inventory from the FOG GUI. @george1421 the FOG Client does not perform “hardware inventory” in the level of telling a user what information the machine has. It simply registers an unregistered machine and allows the admins to approve/disapprove machines in a semi-autonomous methodology. (Not that I think you were saying otherwise, just wanted to make sure the information was more clear.)
Software deployment is not the “strong” element of what FOG does. We do have snapins which could potentially be used to install software, but snapins, in and of themselves, are not really a “software deployment utility”. This would be better suited for some other programs out there. Neither is it a patch management system. Again, you could use snapins to do these things, but this was not what snapins were designed for.
Unattended installation is managed particularly by how you want to manage the installation process. FOG, as @george1421 stated, doesn’t care what “state” your reference machine is in. It only captures the current state of the hard drive in a block level format. I would, personally, recommend using Sysprep (in the case of Windows) to generalize the machine before capture. This will allow you the ability to create what we call a “hardware independent” image. This, however, is not a requirement and FOG will happily capture your disk in any state you feel is sufficient for your needs.
Hardware inventory works just like an imaging task in fog works. (At least if you’re meaning what I think you’re meaning.) You create a task (deploy, capture, or inventory). FOG Uses PXE to load the machine from the network. This passes to a bootfile called iPXE. IPXE then handles checking for the task, and if there is one found booting the machine into the FOS (FOG Operation System) to perform the task. This data is stored in the FOG MySQL database linked to the registered host’s identifier.
Hopefully this helps. @george1421 already stated most of this, but I figured I could potentially help a little too!