Azure DevOps | Build Pipelines Classic

I wish I had seen this months ago! Microsoft's documentation is LACKING to say the least! Helped me immensely!

Hi can you let me know how to use a Predefined variable in classic editor? Can i just use $(Agent.Name) ?? to get the agent name in run time?

Will there be a yaml pipeline video ?

Wow You have explained very well in detail...Thank you much