pathfinding
A* Pathfinding Visualization
See a few video examples of a Unity program that visualizes A* pathfinding in a user friendly way with a tracing option.
Tower Defense Tutorials Part 3
The third video tutorial of a series which takes you through the process of building a tower defense game.
A* Pathfinding Tutorial
Technical talk from Matt Bauer about A* pathfinding in Nauticus Act III.