What is the difference between a project component & a template?

Templates - 

Templates can be thought of as skeletons (or starting points) for threat models which might contain full diagrams, project level threats, or additional information. 

Generally they serve as a starting point for a threat model or a quick method of adding routine infrastructure to an existing threat model. 

Summary: 

• Might contain threats and countermeasures
• Might contain components
• Adding a template will impact the risk ratings of a project (if the template has its own threats)

Project Component - 

Project components are a component within a threat model that references another threat model (or project). They are self contained units and will link back to the original threat model (if the user has permissions to view the other project). 

Summary: 

• Does not contain threats and countermeasures
• IS a component
• Will not influence the risk ratings of the project that it is placed in
• Links back to the original project
• Provides context of how different threat models or projects might interact with each other.