The Freeze option lets you save a snapshot of the dashboard you're viewing. The snapshot will not change or update.
Click the Dashboard Actions menu in the upper right, and select "Freeze". The system will save a snapshot of the dashboard and take you to a page which shows the URL of the frozen dashboard. You can rename it at this time.
Copy the URL and save it to view the snapshot. The frozen dashboard will also be saved in ConAcq Docs.