which can be called actual or close diagonal opposition, or, again, this form:
which can be called actual or close lateral opposition.
In practice they are all one and the same. The Kings are always on squares of the same colour, there is only one intervening square between the Kings, and the player who has moved last "has the opposition."
Now, if the student will take the trouble of moving each King backwards as in a game in the same frontal, diagonal or lateral line respectively shown in the diagrams, we shall have what may be called distant frontal, diagonal and lateral opposition respectively.
The matter of the opposition is highly important, and takes at times somewhat complicated forms, all of which can be solved mathematically; but, for the present, the student should only consider the most simple forms. (An examination of some of the examples of King and Pawns endings already given will show several cases of close opposition.)
In all simple forms of opposition,
when the Kings are on the same line and the number of intervening squares between them is even, the player who has the move has the opposition.