Hardware Inventory and Software Inventory

     When working with SMS inventory features, remember the distinctions between hardware inventory and software inventory. The primary distinction between the two inventory mechanisms is how they work.

     Software inventory works by scanning the disks on each computer to find files and gather information about files. You can also configure software inventory to collect specific files when it finds them.

     Hardware inventory works by querying Windows Management Instrumentation (WMI) for all data from certain WMI classes. WMI includes classes for operating system configuration and entities (such as user accounts), installed software, software configuration, and other objects (such as for the logged on user). These classes are supplements to hardware classes. Hardware inventory collects information about many things besides hardware. For example, it can inventory software by collecting details about programs listed in Add or Remove Programs in Control Panel or programs that have been installed using Windows Installer.

     Because hardware inventory collects a wide variety of data, you might determine that most of your inventory needs can be served by hardware inventory collection alone. Also, with hardware inventory, you can customize inventory to collect more data or different data. Software inventory is useful when you require information about the files on the disks, not necessarily about the software that has been installed. In that sense, software inventory could be called "file inventory."

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