Project represents resources of two primary types: work and material. With Project Server, a hybrid of work resources and generic resources is now available. Work resources always include your human resources and you may use work resources for scheduling equipment or other nonconsumable fixed-asset resources you don’t classify as materials.
Work resources are actual resources you apply to tasks. The system tracks availability of work resources and contains the necessary attributes to support skill-set matching and resource demand and availability management.
Generic resources are pseudo work resources that represent actual resources in a plan. You use generic resources to model staffing demand and for use in skill-set matching and resource substitution. Generic resources don’t accumulate availability.
Material resources are consumable resources that typically represent materials or supplies used during the execution of a task. Material resources are defined in units to suit your requirements and don’t participate in availability calculations.
Because the system has no way to distinguish between nonhuman and human work resources you define, it will count every work resource as a Project Server user in calculating its internal license count requirement. Add as many of these to your license count as required. Consider adding an enterprise resource outline code to distinguish between human and nonhuman resources to separate these two categories in Project views, reports, and Analyzer views.