In the world of aviation, Air Traffic Control can give an IFR pilot instructions to Hold over a particular VOR, Waypoint, or other published Fix.
Hold Entry Visualizer will compute and display the appropriate entry for the hold based on the Hold Radial (or Inbound Heading) and the Aircraft's Current Heading. And best of all, it does this real-time While you're flying by monitoring the ground track of your airplane!

Hold Entry Visualizer can also be used in a 'static' mode for teaching & learning how to make the appropriate entry into a holding pattern. Practicing on the ground rather than in the cockpit simplifies the learning process along with saving time and money.