How does a snow fence work?

You've probably seen these orange fences here and there this winter. What do they do and how do they work?

Snow Fence Installation Instructions

How does a snow fence work?

Transportation Defined: Snow Fence

Learn How to Use Snow Fencing & Snow Drift Fencing - US Netting

Snow fences: How do they work? What are they? Where did they come from? (PHOTOS)

Snow fence placement question

NCR-191

Install snow fence properly to reduce drifting

How do Snow Fences Work?