Windows Driver Policy - What is Active Use

Hi, I'm using an unsigned Windows driver. In the https://support.microsoft.com/en-us/windows/the-windows-driver-policy-ecd2a78c-750c-415d-93f2-e37302ce0443 article, what is the definition of "Active Use" in the Evaluation Criteria "Your device must have accumulated 100 hours of active use"? 

And, is there a way to see my computer's remaining number of Active Use hours in Evaluation mode somehow?

Thanks!