Following a path

Before diving into A*, which is a procedural approach to pathfinding, we'll implement a more rudimentary waypoint-based system. While more advanced techniques, such as the aforementioned A* method or Unity's NavMesh, will often be the preferred method for pathfinding, looking at a simpler, more pure version will help set the foundation for understanding more complex pathfinding approaches. Not only that, but there are many scenarios in which a waypoint-based system will be more than enough, and will allow more fine-tuned control over your AI agent's behavior. 

In this example, we'll create a path, which is made up of individual waypoints. For our purposes, a waypoint is simply a point in space with an X, Y, and Z value; we can simply use a Vector3 to represent this data. By making a serialized array of Vector3 in our script, we'll be able to edit the points in the inspector without much fuss. If you want to challenge yourself and tweak this system to be a bit more user-friendly...