I don't need to test my programs. I have an error-correcting modem.
PathNodes are the most commonly used navigation points when building a navigation network for AI-controlled moving entities like bots and monsters. They are basically navigation points with no purpose other than marking a node of the navigation network. Note that pickup items such as health, weapons, ammo and powerups create their own navigation points (invisible InventorySpot actors) when paths are built, so you can use pickup items (Inventory (UT) and Pickup for UT and UT200x respectively) instead of pathnodes.