Paths are quite simple files that define a series of waypoints that make up a path that the enemies will follow across the screen. These values are specified in x and y coordinate pairs (so the x and y entries are paired together in order to make the path). Rather than using absolute coordinates, these points are specified using values from zero to 1 and are fractions of the game window size. That way the window can be any size and the path will still work correctly.
x - An x coordinate specified as a fraction of the screen width.
y - A y coordinate specified as a fraction of the screen height.