Physical Assets
A physical asset is an asset that represents a single, physical object - such as a person, a vehicle, sensor or machine.
A physical asset may also have sub-components, but it represents something you can actually see and touch.
Alternatively, logical assets are assets that represent concepts rather than physical objects - these are often used to group and categorise your physical assets.
For example, you may want to place all of your network hardware into a group - in this case, you would have several physical assets in the network equipment itself, and then the logical asset 'Network Equipment'.