What is the effect of using "move();" when at the edge of the grid?

Using "move();" when Karel is at the edge of the grid results in Karel attempting to move into a wall, which means Karel will encounter an obstacle that prevents further movement. This behavior is critical in understanding how Karel operates within its environment.

Karel is programmed to follow specific rules that simulate the actions of a robot moving on a grid. When Karel reaches the edge (or a wall), the "move();" command does not allow Karel to move outside the boundaries defined by the grid, which means the command will trigger a situation where Karel cannot proceed further in that direction.

This reinforces the idea that Karel cannot move into spaces that are not defined in its grid structure, thus keeping the character within the allowed limits and making it essential for programming movements accurately without causing Karel to go out of bounds or into non-existent spaces.